Endocrinology Vol. 139, No. 12 5015-5033
Copyright © 1998 by The Endocrine Society
Comparative Distribution of Vasopressin V1b and Oxytocin Receptor Messenger Ribonucleic Acids in Brain1
Christopher Vaccari,
Stephen J. Lolait and
Nancy L. Ostrowski
Section on Behavioral Pharmacology (C.V., N.L.O.), Biological
Psychiatry Branch and Laboratory of Cellular and Molecular Regulation
(S.J.L.), National Institute of Mental Health, National Institutes of
Health, Bethesda, Maryland 20892-4090
Address all correspondence and requests for reprints to: Nancy L. Ostrowski, Ph.D., Eli Lilly and Co., Lilly Corporate Center, Building 22, Drop Code 2244, Indianapolis, Indiana 46285.
 |
Abstract
|
|---|
The comparative distributions of the vasopressin V1b receptor (V1bR)
and the oxytocin receptor (OTR) messenger RNAs (mRNAs) are described in
male rat brain using in situ hybridization histochemistry.
V1bR transcripts were present in forebrain and hypothalamus and were
less abundant in mid- and hindbrain regions, similar to the gradient
observed with OTR transcripts. Microscopic analyses indicated that V1bR
expressing cells typically demonstrated the morphology of neurons and
confirmed V1bR gene expression in regions including the olfactory bulb,
supraoptic, suprachiasmatic, and dorsomedial hypothalamic nuclei,
piriform and entorhinal cortices, hippocampus, substantia nigra, and
dorsal motor nucleus of the vagus. Most regions that expressed V1bR
mRNA also expressed OTR mRNA, although OTR gene expression was much
more extensive than that of the V1bR. V1bR and OTR mRNA distributions
were distinct from each other and from that of the V1a receptor mRNA in
brain. A few brain regions express only V1bR transcripts such as the
dorsomedial hypothalamic nucleus and the external plexiform layer of
the olfactory bulb. Other brain regions, such as the fields of Ammons
horn, the suprachiasmatic nucleus, the substantia nigra pars compacta,
and the piriform cortex express mRNAs that encode all three receptor
subtypes (V1a, V1b, and OTR), whereas brain areas including the red
nucleus and supraoptic nucleus express V1bR and OTR transcripts only.
These data suggest functional specialization of the V1b, OTR and V1a
receptors in brain.
 |
Introduction
|
|---|
CENTRAL AND PERIPHERAL
effects of arginine vasopressin (AVP) are mediated by at least three
subtypes of G protein-linked membrane-bound vasopressin receptors.
These receptors fall into two classes based on second messenger
cascades and pharmacological properties. Activation of the V2
vasopressin receptor results in the stimulation of adenylate cyclase
(1) and mediates the well established antidiuretic properties of AVP in
kidney, where V2 receptors (V2R) (2) and V2R messenger RNA (mRNA) (3)
are abundant. Stimulation of the V1 class of receptor subtypes results
in the hydrolysis of phosphatidyl inositol and an increase in cytosolic
calcium (4). The V1a receptor (V1aR) mediates the vasoconstrictor and
hepatic glycogenolytic actions of AVP. This receptor has been cloned
(5), and its mRNA has been visualized throughout brain (3, 6), liver,
and kidney (3, 7) using in situ hybridization
histochemistry. The distribution of the V1aR mRNA corresponds to the
distribution of radiolabeled binding sites for AVP and selective V1aR
ligands (2, 8); this receptor is thought to be the predominant AVP
receptor in brain (9, 10).
A second subtype of the V1 class, the V1b receptor (V1bR), has been
characterized in the anterior pituitary, where it regulates
AVP-mediated ACTH release by potentiating the effects of CRH (11, 12).
Recent studies have detected V1bR mRNA through RT-PCR in the thymus,
heart, lung, spleen, kidney, uterus, and breast (13, 14). Furthermore,
Lolait et al. (13) detected V1bR mRNA in several
hypothalamic and extra-hypothalamic brain regions. The cellular
distribution has not been characterized to date.
Receptors for oxytocin are highly homologous to vasopressin receptors,
bind both oxytocin and AVP with high affinities, and have been
localized throughout brain including regions where we have detected
V1bR mRNA (8). The OTR mRNA distribution has been characterized in rat
brain using only the human OTR gene-derived ribonucleic acid probes
(riboprobes) (15). In this paper, we describe the distribution of rat
V1bR-derived mRNA in male Sprague-Dawley rat brains using in
situ hybridization histochemistry and compare it to the
distribution of rat OTR gene expressing cells.
 |
Materials and Methods
|
|---|
To determine V1bR mRNA localization, two normal adult male
Sprague-Dawley rats (250 g) were euthanized by decapitation, their
brains rapidly removed and frozen on crushed dry ice and whole brains
sectioned for in situ hybridization. Distributions were
confirmed in brains of an additional four adult males that served as
control animals in another experiment (not reported here). Similarly,
four adult male rats were used to characterize the whole brain
distribution of the OTR mRNA, and distributions were confirmed in
brains of an additional six male animals used as controls in another
experiment.
All work was done in accordance with National Institutes of Health
guidelines for animal use and care and following approvals of protocols
by the National Institute of Mental Health Animal Care and Use
Committee.
Probes
The region of the AVP and OT receptor genes
demonstrating the least homology, (i.e. a sequence
corresponding to the third intracellular loop of the receptors) was
included in each of the riboprobes used. The V1bR probe was a 618-bp
Asp718/blunt end sequence (extending from the second intracellular loop
to the seventh transmembrane region of the rat cDNA) subcloned into
pGEM3Z (13). The OTR cDNA was a 633-bp PCR fragment (spanning the
second to sixth transmembrane regions) subcloned into
pGEM4Z (16). Sense and antisense probes for both V1bR and OTR
constructs were synthesized using 35S radiolabeled-UTP. One
additional V1bR probe and two additional OTR probes were prescreened in
liver, brain, kidney, uterus, and spleen. All probes yielded similar
distributions of their respective mRNAs. The probes used in these
experiments demonstrated the greatest signal to noise ratios indexed by
the density of selective tissue labeling relative to
background [(Antisense-background)(sense-background)]. In addition
to "sense" control experiments, V1b, V1a, V2, and OTR transcript
labeling was measured in liver, kidney and pituitary.
In situ hybridization histochemistry
Whole brains were cryosectioned (24 µm-thick), thaw-mounted
(three per slide) onto glass microscope slides subbed with
gelatin-chrome-alum, and frozen at -70 C until used. Slide-mounted
sections were rapidly thawed to room temperature, immersed in 4%
formaldehyde solution, treated with acetic anhydride, rinsed,
dehydrated, and delipidated in a series of graded ethanol solutions
followed by immersion in chloroform. Slide-mounted tissue was covered
with 35S-labeled probe (1.25 million cpm per slide),
coverslipped, and incubated for 22 h at 55 C. Posthybridization
washes consisted of a series of 4x, 2x, 1x, and 0.5x saline-sodium
citrate buffer (SSC) washes, incubation in a 20 µg/ml RNase solution
at 37 C, followed by a series of 0.1x SSC washes containing
dithiothreitol at 65 and 67.5 C. Tissue was dehydrated in a series of
graded alcohol solutions containing 300 mM ammonium
acetate, then dried, apposed to autoradiographic film (Kodak B-Max;
Eastman Kodak, Rochester, NY), and exposed for 14
days.
To visualize the hybridization signal at the cellular level, slides
were dipped in nuclear emulsion (Kodak NTB-2; Eastman Kodak) and exposed at 4 C for 3 (V1bR) or 4 (OTR) months. Slides
were developed (Kodak D19; Eastman Kodak) and stained with
thionin, and in some cases, counterstained with eosin and coverslipped.
Slides were examined with a light microscope, under bright and dark
field illumination. Distributions of cells expressing the respective
mRNAs were plotted onto templates modified from the rat brain atlas of
Paxinos and Watson (17) using Adobe Photoshop and templates
similar to those used for V1aR mRNA (6).
Data analysis
Hybridization signal was quantified using the NIH Image program.
Optical densities (corrected for background signal) were obtained for
the left and right hemispheres for each region analyzed. To assess the
amount of hybridization signal in emulsion-dipped slides, individual
grains were counted. Cells covered by at least two times as many grains
as background were designated as expressing the given receptor
mRNA.
Hybridization experiments for OTR and V1bR mRNAs were conducted
separately, permitting qualitative, but not quantitative
comparisons.
 |
Results
|
|---|
Specificity of the probes
Control experiments showed that liver expressed only V1aR
transcripts, whereas pituitary expressed V1aR, V1bR, and OTR mRNAs in
different cell populations. Renal tissue was the most informative, in
that all four transcripts were differentially distributed (data not
shown): V1aR mRNA was localized primarily to vascular elements
including vasa recta; V2R mRNA was abundant in the collecting ducts and
thick ascending limbs of the Loops of Henle; OTR transcripts were found
in macula densa cells in renal cortex, and, in animals pretreated with
estrogen, in S2 and S3 segments of proximal tubules (see Ref. 16). V1bR
mRNA was not detected in parenchymal tissue but was localized in some
large renal blood vessels and in the transitional epithelium of the
pelvic wall. Estrogen treatment neither induced nor changed V1bR
labeling in kidney.
V1bR sense labeling was undetectable except in the dentate gyrus of the
hippocampus where low levels of signal were detected similar to those
observed using the antisense probe. Microscopic evaluation failed to
localize dentate antisense or sense labeling to cell bodies; antisense
levels did not reach criteria for specific labeling. OTR sense labeling
was typically near film background levels. Film autoradiographs showed
above-background levels of sense labeling in the dentate gyrus and the
cerebellum. In the dentate, antisense accumulation over cell soma
indicated specific labeling.
Table 1
presents brain regions that
express V1bR mRNA. Regions are rank-ordered according to film optical
density measurements for the V1bR hybridization signal. The
coexpression of OTR mRNA was determined by microscopic analyses. The
dorsomedial hypothalamic nucleus and the external plexiform layer of
the olfactory bulb express only V1bR mRNA. However, most other regions
that express V1bR transcripts also express the OTR gene.
Figure 1
presents a schematic diagram of
the localizations of the V1bR and OTR transcripts in emulsion-dipped
tissues. Qualitative differences were observed in the hybridization
signals of V1bR and OTR mRNAs. Specifically, in regions where V1bR mRNA
was detected, signal intensity was usually homogeneous from cell to
cell, with a preponderance of grains localized to the nucleus and soma
of the cells. Signal intensity varied slightly from cell to cell, and
film densities typically reflect the number of cells in a given region
expressing the gene. In contrast, the OTR hybridization signal
intensity varied from region to region and from cell to cell within
specific regions. The signal was not only localized to nuclei and soma
but also to the cytoplasm of the cell.




View larger version (176K):
[in this window]
[in a new window]
|
Figure 1. Diagram of the distribution of arginine
vasopressin V1b and oxytocin receptor mRNA expressing cells in male rat
brain. Distributions were plotted based on inspection of nuclear
emulsion-dipped brain sections (34 month exposures) under bright and
darkfield conditions. OTR mRNA labeled cells are presented on the
left, and V1bR mRNA labeled cells on the right.
Abbreviations correspond to those in Paxinos and Watson (17 ): 2, 610,
cerebellar lobules; 2n, optic nerve; 3V, third ventricle; 4V, fourth
ventricle; 4&5, cerebellar lobules; 6, abducens nucleus; 7, facial
nucleus; 7n, facial nerve; 8n, vestibulocochlear nerve; 12, hypoglossal
nucleus; 12n, root of hypoglossal; ac, anterior commissure; ACB,
accumbens nucleus; aci, anterior commissure, intrabulbar; Aco, anterior
cortical amygdala nucleus; Acs7, accessory facial nucleus; AHC,
anterior hypothalamic area; AHi, amygdalo-hippocampal area; AHiPM,
amygdala-hippocampal area, posteromedial part; AI, agranular insular
cortex; Am, amygdala nuclei; Amb, ambiguous nucleus; AOD, anterior
olfactory nucleus, dorsal part; AOM, anterior olfactory nucleus, medial
part; AOP, anterior olfactory nucleus, posterior part; AOV, anterior
olfactory nucleus, ventral part; APir, amygdalo-piriform transition
area; APT, anterior pretectal nucleus; Aq, cerebral aqueduct; Arc,
arcuate nucleus; AV anteroventral thalamic nucleus; BST, bed nucleus of
the stria terminalis; bsc, brachium of the superior
colliculus; CA1-3, fields of CA 1-3 of Ammons horn; CB, cerebellum;
cc corpus callosum; CG, central gray; Cg, cingulate cortex; CIC,
central nucleus of the inferior colliculus; CL, claustrum; CnF,
cuneiform nucleus; cp, cerebral peduncle; CPu, caudate putamen
(striatum); Crus 1, Crus 1 of the ansiform lobule; ctg, central
tegmental tract; D3V, dorsal third ventricle; DA, dorsal hypothalamic
area; DG, dentate gyrus; DLG, dorsal lateral geniculate nucleus; Dll,
dorsal nucleus of the lateral lemniscus; DMC, dorsomedial hypothalamic
nucleus, compact part; DMSp5, dorsomedial spinal trigeminal nucleus;
DR, dorsal raphe nucleus; DSC, lamina dissecans entorhinal cortex; ec,
external capsule; ECIC, external cortex of the inferior colliculus;
Ecu, external cuneate cortex; Ent, entorhinal cortex; EP,
entopeduncular nucleus; EPI, external plexiform layer of the olfactory
bulb; f, fornix; fi, fimbria; Fr, frontal cortex; FStr, fundus striati;
Gi, gigantocellular reticular nucleus; GP, globus pallidus; HDB,
nucleus of the horizontal limb of the diagonal band; Hil, hilus of the
dentate gyrus; I, intercalated nuclei of the amygdala; ic, internal
capsule; icp, inferior cerebellar peduncle; IGr, internal granular
layer of the olfactory bulb; InCo, intercollicular nucleus; IntA,
interposed cerebellar nucleus; IOC, inferior olive, subnucleus C of the
medial nucleus; IPI, interpeduncular nucleus, intermediate; IPC,
interpeduncular nucleus, caudal; Ip1, internal plexiform layer of the
olfactory bulb; IRt, intermediate reticular nucleus; LC, locus
coeruleus; LH, lateral hypothalmic area; LHb, lateral habenula nucleus;
LO, lateral orbital cortex; LPB, lateral parabrachial nucleus; LPGi,
lateral paragigantocellular nucleus; LR4V, lateral recess of the fourth
ventricle; LRt, lateral reticular nucleus; LS, lateral septal nucleus;
LSO, lateral superior olive; LV, lateral ventricle; LVe, lateral
vestibular nucleus; mcp, middle cerebellar peduncle; MCPO,
magnocellular preoptic nucleus; ME, median eminence; me5, mesencephalic
trigeminal tract; mfb, medial forebrain bundle; mfba, medial forebrain
bundle "a" component; MGV, medial geniculate nucleus; MHb, medial
habenula nucleus; MI, mitral cell layer of the olfactory bulb; ml,
medial lemniscus; mlf, medial longitudinal fasciculus; MM, medial
mammillary nucleus, medial part; MnR, median raphe nucleus; Po5, motor
trigeminal nucleus; MP, medial mammillary nucleus, posterior part; MPO,
medial preoptic nucleus; MVe, medial vestibular nucleus; Oc, occipital
cortex; ON, olfactory nerve layer; Op, optic nerve layer of the
superior colliculus; ox, optic chiasm; Par, parietal cortex; PaV,
paraventricular nucleus of the hypothalamus; PCRtA, parvocellular
reticular nucleus, part; Pe, periventricular nucleus of the
hypothalamus; PF, parafascicular thalamic nucleus; PFI, paraflocculus;
PH, posterior hypothalamic area; Pi, pineal gland; Pir, piriform
cortex; PLCo, posterolateral cortical amygdala nucleus; PMCo,
posteromedial cortical amygdala nucleus; PMD, premammillary nucleus,
dorsal part; Pn, pontine nucleus; PnC, pontine reticular nucleus,
caudal part; PnO, pontine reticular nucleus, oral part; PoDG, polymorph
layer of the dentate gyrus; PPT, posterior pretectal nucleus; Pr5VL,
principal trigeminal sensory nucleus, ventrolateral part; Prb, nucleus
of Probsts bundle; PRh, perirhinal cortex; PrH, prepositus
hypoglossal nucleus; PrS, presubiculum; PVA, paraventricular nucleus of
the thalamus, anterior part; py, pyrimidal tract; RCh, retrochiasmatic
area; RMC, red nucleus, magnocellular part; RMg, raphe magnus nucleus;
ROb, raphe obscurus nucleus; RPC, red nucleus, parvocellular part; RPO,
rostral periolivary region; RR, retrorubral nucleus; RRF, retrorubral
field; RSA, retrosplenial agranular cortex; Rt, reticular thalamic
nucleus; RtTg, reticulo-tegmental nucleus of the pons; S, subiculum;
s5, sensory root of the trigeminal nerve; scc, splenium of the corpus
callosum; SCh, suprachiasmatic nucleus; scp, superior cerebellar
peduncle, brachium conjunctivum; SFO, subfornical organ; SI, substantia
inominata; Sim, simple lobule; sm, stria medullaris of the thalamus;
SNR, substantia nigra, reticular part; SNC, substantia nigra, compact
part; SO, supraoptic nucleus; Sol, nucleus of the solitary tract; sol,
solitary tract; SOR, supraoptic nucleus, retrochiasmatic; SPTg,
subpeduncular tegmental nucleus; SPO, superior periolivary nucleus;
sp5, spinal trigeminal nucleus; Sp51, spinal trigeminal nucleus, caudal
part; Sp5O, spinal trigeminal nucleus, oral part; st, stria terminalis;
Stg, stigmoid hypothalamic nucleus; STh, subthalamic nucleus; SuM,
supramammillary nucleus; Te, temporal cortex; tfp, transverse fibers of
the pons; TM, tuberomammillary nucleus; ts, tectospinal tract; Tu,
olfactory tubercle; tz, trapezoid body; VCA, ventral cochlear nucleus,
anterior part; VEn, ventral endopiriform nucleus; VL, ventrolateral
thalamic nucleus; VLO, ventrolateral orbital cortex; VMH, ventromedial
nucleus of the hypothalamus; VP, ventral pallidum; VPM, ventral
posteromedial thalamic nucleus; VTA, ventral tegmental nucleus (Tsai);
VTg, ventral tegmental nucleus (Gudden); ZI, zona incerta.
|
|
Microscopic analyses confirmed localization of both V1bR and OTR
transcripts to cell populations in the olfactory bulb, forebrain,
hypothalmus, hippocampus, midbrain, and hindbrain. Both receptor mRNAs
were more abundant in anterior than in caudal brain. In addition,
scattered cells were detected on emulsion-dipped slides that were
undetectable on film autoradiographs. V1bR-labeled cells tended to be
large, with large, round nuclei, and demonstrated light staining Nissl
substance with a granular appearance. OTR-labeled cells demonstrated no
consistently unique morphology.
Olfactory bulb
V1bR mRNA was found in periodically spaced cells in the mitral
cell layer (Fig. 2
, A and C) of the
olfactory bulb with densest label in the ventrolateral bulb. The
external plexiform layer weakly labeled. In contrast, OTR mRNA was
distributed throughout the granule cell layer, with a denser expression
in the mitral cell layer. The OTR gene was expressed in some
periglomerular cells (See Fig. 2
, B and D).

View larger version (146K):
[in this window]
[in a new window]
|
Figure 2. Olfactory bulb. V1bR (left) and OTR
(right) mRNA distributions differ in the olfactory bulb.
Darkfield (A; 400x) and corresponding brightfield (C; 400x)
photomicrographs show V1bR transcripts are in large, lightly
thionin-stained cells at the periphery of the mitral cell layer.
Granule cells (bottom of photograph) exhibit lower levels of
signal. In contrast, OTR mRNA is dispersed throughout the olfactory
bulb (B; 25x) with hybridization signal concentrated throughout the
mitral cell layer (arrow), moderate in periglomerular cells
(arrowhead), and least dense in the granule cells
(bottom of photograph in D; 400x). Silver grains appear
white in darkfield and black in brightfield
images.
|
|
Forebrain
V1bR transcripts were found in the tenia tecta and piriform
cortex (Pir). In the tenia tecta, label was greatest in the most
anterior sections, and decreased caudally. The entire piriform cortex
labeled, with strongest signal detected in the anterior forebrain and
decreasing in intensity caudally. Several cortical areas expressed
light to intermediate hybridization signal, including the outer layers
of agranular insular cortex, ventrolateral orbital cortex, lateral
orbital cortex, and occasional scattered cells in the parietal and
frontal cortices. Cells in the outer layers of the ventrolateral and
lateral aspects of the orbital cortex lightly labeled, primarily around
3.7 mm anterior to Bregma. At this level, a string of labeled cells
coursed around the superficial layers of cortex, with label densest in
the agranular insular cortex and more scattered in cells of the
parietal and frontal cortices.
The anterior olfactory nucleus (Fig. 3
),
tenia tecta, and piriform cortex expressed high levels of OTR mRNA.
V1bR transcripts were not visualized in the anterior olfactory nucleus.
The distribution of OTR mRNA was similar to that of V1bR mRNA in the
piriform cortex (see Fig. 4
) but, whereas
OTR transcripts were abundant in the olfactory tubercle, V1bR mRNA was
not detected.

View larger version (116K):
[in this window]
[in a new window]
|
Figure 3. Anterior olfactory nucleus. Brightfield (A; 20x)
and darkfield (B; 20x) photomicrographs show OTR transcripts are in
all regions of the anterior olfactory nucleus (AON) with denser signal
in the ventral quadrants. Arrow points to rostral piriform
cortex. Note low levels of OTR mRNA in overlying cortex.
|
|

View larger version (95K):
[in this window]
[in a new window]
|
Figure 4. Piriform cortex. Photomicrographs depicting OTR
mRNA labeling in the piriform cortex (PIR) and lateral olfactory
tubercle (t, open arrow). A (50x), brightfield
photomicrograph showing the lateral olfactory tract (LOT), piriform
cortex (PIR), and lateral aspect of the olfactory tubercle (t). B
(50x), corresponding darkfield photo. V1bR transcripts were found
throughout the piriform cortex but were not expressed in the olfactory
tubercle (not shown).
|
|
OTR expression in frontal cortex exhibited a gradient with scattered
cells in layers 2 and 3 labeling throughout; deeper cells exhibited
less intense label and were more sparsely distributed. Cortical
expression was less intense at more caudal levels. Cingulate cortex
expressed moderate levels of transcripts.
The lateral septal nucleus, ventral pallidum, globus pallidus, and
accumbens nucleus expressed very low densities of the OTR gene. In the
caudate putamen, only the dorsomedial portion expressed low levels of
the OTR gene.
Hypothalamus and diencephalon
V1bR mRNA was in numerous cells of the suprachiasmatic and
supraoptic nuclei (SON) of the hypothalamus (Fig. 5
, A and C). There was light labeling of
cells in the periventricular nucleus. Grain counts were slightly
elevated above background but did not reach criterion for labeling in
the paraventricular nucleus of the hypothalamus (Fig. 6
, A and C). V1bR transcripts were
evident in cells of the medial preoptic area, lateral hypothalamus,
anterior amgydala, and the region lateral to the SON.

View larger version (129K):
[in this window]
[in a new window]
|
Figure 5. Supraoptic and suprachiasmatic nuclei of the
hypothalamus. V1bR (left) and OTR (right)
transcripts have similar distributions in the SON and SCN depicted in
the top darkfield panels (A and B, 25x). Silver grains appears
white. Greater magnification (630x) of cells in the SON (C,
D) and SCN (E and F) show differences in V1bR and OTR labeling
patterns. Note the clustering of V1bR label near thionin-stained nuclei
in C and E. In contrast, OTR mRNA, while densest over stained nuclei,
tends to be more diffusely localized (D and F).
|
|

View larger version (148K):
[in this window]
[in a new window]
|
Figure 6. PVN. The PVN expresses OTR mRNA (right)
but not V1bR mRNA (left). A and B are brightfield
photomicrographs (50x) and C and D are corresponding darkfield
photomicrographs of the PVN (50x). Both the magnocellular (m) and
parvocellular (p) regions express OTR hybridization signal. E and F,
high magnification (630x) photos of cells at the border between the
magnocells and parvocells. Note background levels of V1b signal over
cells (arrows) and diffuse OTR label over individual nuclei
(arrows).
|
|
More caudally, label was detected in the hypothalamus at approximately
3.3 mm posterior to Bregma, where V1bR mRNA transcripts were well
labeled in the compact portion of the dorsomedial hypothalamic nucleus.
The ventromedial nucleus of the hypothalamus did not express V1bR mRNA.
Further caudally, signal was seen in the tuberomammillary nucleus, with
light labeling in the dorsal premammillary nucleus.
At approximately 4.3 mm caudal to Bregma, labeled cells of the piriform
cortex and cells in the perirhinal cortex appeared contiguous. The
posteromedial cortical amygdala nucleus (PMCo) expressed moderate
amounts of V1bR mRNA, and the posterolateral cortical amygdala nucleus
(PLCo) expressed low levels.
In thalamus, only a few cells in the anterior paraventricular nucleus
expressed hybridization signal.
Similar to the distribution of V1bR mRNA, OTR transcripts were also
abundant in the suprachiasmatic and supraoptic nuclei (See Fig. 5
, B
and D). OTR, but not V1bR mRNA, was expressed in the paraventricular
nucleus (Fig. 6
).
OTR transcripts were densest in the ventromedial nucleus (VMN) of the
hypothalamus (Fig. 7
), with the
ventrolateral division expressing higher levels of transcript than the
dorsomedial division. Notably, the entire VMN, ranging from the most
anterior to the caudal poles, expressed OTR signal.

View larger version (157K):
[in this window]
[in a new window]
|
Figure 7. Ventromedial nucleus. The top left
darkfield image (A, 50x) shows that V1bR transcripts are undetectable
in the ventromedial nucleus of the hypthalamus (VMN). High
magnification of VMN cells from the ventrolateral subdivision of this
nucleus confirms sparse label. Note low levels of grains over cells in
D (arrow and arrowhead) and G (arrow
and arrowhead). In contrast, the ventrolateral (vl) VMN, but
not the dorsomedial (dm) VMN from an adult male shows abundant OTR gene
expression (B and C, 50x). High magnification brightfield (E) and
darkfield (H) images show label surrounding cells. The entire VMN
expresses OTR transcripts; both the anterior (not shown) and posterior
(p) portions (C) of the VMN express dense accumulations of transcripts
over individual cells (F, arrow) and in the surround (I).
High magnifications are 630x.
|
|
OTR gene expression could be visualized in scattered cells
throughout the ventral hypothalamus with high expression in the
retrochiasmatic area, the premammillary nucleus and mammillary complex,
the arcuate nucleus, and periarcuate area. A restricted portion
(probably intermediate) of the bed nucleus of the stria terminals
expressed some of the densest OTR mRNA labeling in brain. The bed
nucleus of the stria terminalis and SON expressed greater levels of OTR
transcripts than the median preoptic nucleus, the horizontal nucleus of
the diagonal band, the medial preoptic nucleus, and the olfactory
tubercle. The medial habenula exhibited moderate gene expression. Other
regions that expressed lower levels of OTR hybridization signal
included the central nucleus of the amygdala, ventral subiculum,
cortical and medial amygdala, subfornical organ, and entorhinal
cortex.
Thalamic OTR transcript labeling was sparse with detectable signal
primarily in the anterior paraventricular nucleus of the thalamus (see
Fig. 1
).
Hippocampus
V1bR mRNA was most abundant in CA2. It was uniformly expressed in
CA1 (Fig. 8
, A, C, and E) whereas signal
intensity in CA3 became progressively greater more caudally. The
dentate gyrus showed low levels of V1bR gene product that could not be
localized to cell bodies and did not reach criteria for specific
labeling.

View larger version (150K):
[in this window]
[in a new window]
|
Figure 8. Hippocampus. OTR mRNA (right) is more
abundant in the hippocampus than V1b mRNA (left). OTR
transcripts are moderately dense in the dentate gyrus (DG) (D, 25x).
As can be discerned in panel D, labeling is slightly more abundant in
CA2 than CA1 and CA3. Similarly, V1bR transcripts are slightly greater
in CA2, followed by CA3, CA1, and the DG (C). E and F, High
magnification (400x) of cells sampled at arrows in A and B.
Note the restricted localization of V1bR signal and the diffuse
distribution of the OTR hybridization signal in CA2 depicted in E and
F, respectively.
|
|
Notably, OTR transcripts were evident in the cell-dense areas of the
hippocampus with the dentate gyrus, CA2 and CA3 expressing greater
levels than CA1 (Fig. 8
, B, D, and F).
Midbrain
Low levels of V1bR mRNA were in cells in the ventral tegmental
area (VTA) and the substantia nigra, pars compacta (SNC),
whereas only occasional cells expressed transcript in the pars
reticulata (Fig. 9
). The magnocellular
aspect of the red nucleus (Fig. 10
) and
outer layers of the entorhinal cortex moderately labeled. Labeling in
the entorhinal cortex became stronger progressing caudally and extended
into the deeper layers of cortex. Strong labeling of V1bR mRNA was
evident in the dorsal raphe nucleus, with lighter labeling in the
amgydala-piriform transition area.

View larger version (142K):
[in this window]
[in a new window]
|
Figure 9. Substantia nigra and ventral tegmental area. Both
V1bR and OTR transcripts are expressed in the SNC and ventral tegmental
area (VTA). Note sparse V1bR mRNA in the medial SNC and VTA in
darkfield photomicrograph in A and C (magnification, 25x). OTR-labeled
cells can be discerned at 50x magnification (B and D) in the region
corresponding to the pars compacta (arrows, C, D). Higher
magnification (630x, E and F) shows sparse V1bR (E) and diffuse OTR
gene expression (F) in individual cells in the medial SNC
(arrows).
|
|

View larger version (126K):
[in this window]
[in a new window]
|
Figure 10. Red nucleus. V1bR-mRNA expressing cells in the
red nucleus are typical of many cells that express V1bR mRNA. As can be
seen in A (10x magnification) the cells tend to lightly stain with
thionin, have large cell bodies (B, 400x) and have nuclei with a
lightly granular appearance. V1bR-labeled cells in the red nucleus
appear to correspond to the magnocells; cells with other morphologies
did not label. Large, scattered, labeled cells, similar to those
depicted here (arrows), were occasionally detected
throughout the midbrain and cortex.
|
|
OTR mRNA was detected in the red nucleus, dorsal raphe nucleus, SNC
(Fig. 9
), VTA and the central gray.
Hindbrain
Both V1bR and OTR transcripts were less abundant in hindbrain than
more anterior brain regions. Pontine nuclei exhibited moderate V1bR
expression, whereas light to intermediate levels of V1bR signal were
detected in the locus coeruleus, facial nucleus, dorsal motor nucleus
of the vagus (DMV), gigantocellular reticular nucleus, lateral
reticular nucleus (LRt), and trigeminal nucleus (oral and interpolar
portions). Labeled cells in the regions of the DMV appeared contiguous
with a few labeled cells in the nucleus of the solitary tract (NTS) and
hypoglossal nucleus in emulsion-dipped slides.
Hindbrain OTR transcripts were highest in the dorsal motor nucleus of
the vagus (DMV) and Nucleus O. The locus ceruleus, and trigeminal and
lateral reticular nuclei expressed intermediate levels of transcript,
whereas the pontine, gigantocellular reticular, medial vestibular,
hypoglossal nuclei, and the lateral aspect of the inferior olive
nucleus expressed low hybridization signal.
OTR mRNA was also detected at low levels in blood vessels on the
ventral surface of the brain, in the pineal, in intermittent large
cells (may be Purkinje cells) at the border of the granule cell layer
and in the molecular cell layer of the cerebellum, and cells in the
lining of the ventricular walls.
 |
Discussion
|
|---|
Until recently, pharmacologic discrimination of the V1a, V1b, V2,
and OTR receptors relied heavily on radioligand binding assays using
AVP, OT, and relatively selective agonists and antagonists (8, 10, 11, 18, 19, 20). With the cloning of all four of the rat complementary DNAs for
AVP and OT receptors (V1a: 5; V1b: 13; V2: 21; OTR: 22) in
situ hybridization can provide a method of localizing and
distinguishing among cells that express the genes encoding these
receptors. Further, in situ hybridization histochemistry
provides a sufficiently high level of resolution to begin to address
questions regarding the phenotypes of cells in the brain that express
the AVP and OT receptor subtypes; whether there is regional overlap in
their distributions; and, eventually, whether individual cells
coexpress these receptor mRNAs. In this paper we described the
localization of the V1bR and OTR mRNAs in rat brain. We have previously
reported the localization of the V1aR mRNA (6).
Localization of V1bR mRNA
Cells that express V1bR transcripts are present in anatomically
discrete brain regions (e.g. suprachiasmatic nucleus, the
red nucleus, the substantia nigra pars compacta, and the
supraoptic nucleus) and have the morphology of neurons. V1bR
transcripts are less abundant and more restricted in their distribution
than the OTR and the V1aR transcripts. Although the OTR gene is
expressed by numerous cells and in regions that express V1bR mRNA, the
overall distribution pattern supports distinct receptor gene products.
Specifically, the anterior olfactory nucleus and the ventromedial
nucleus of the hypothalamus, regions that expressed the highest levels
of OTR transcripts did not express V1bR mRNA, excluding the possibility
that the V1bR probe cross-hybridized with OTR mRNA. Furthermore, the
brain distribution of V1bR transcripts also differed from that of V1aR
mRNA making it improbable that the V1bR riboprobe cross-hybridized with
V1aR mRNA. Again, V1bR transcripts were undetectable in the lateral
septum and the anterior olfactory nucleus, two regions that express
high levels of V1aR transcripts (6). In contrast to a previous study,
(23), we have not detected specific labeling of V2R mRNA in adult rat
brain (6, Ostrowski, unpublished).
Following the cloning of the V1bR from pituitary cDNA libraries, the
receptor mRNA was detected by RT-PCR in the rat thymus, heart, lung,
spleen, kidney, uterus, and breast (13, 14). Lolait et al.
(13) have published RT-PCR data providing evidence for extrapituitary
expression of V1bR mRNA in the olfactory bulb, caudate putamen, septum,
cortex, hypothalamus, hippocampus, and cerebellum in the rat. Here, we
visualized V1bR transcripts in cells in regions shown by RT-PCR to
express V1bR mRNA with the exception of the caudate putamen, cerebellum
and septum where we failed to detect transcript. While the reason for
this discrepancy remains unclear, it is possible that the number of
copies of transcripts were too low to be visually detected using
emulsion autoradiography or that the RT-PCR samples included adjacent
V1bR-expressing tissues. Confirmation of expression of the V1bR protein
throughout brain will require the development of selective or specific
V1bR radioligands and/or V1bR-specific antibodies.
Permutations in the patterns of coexpression of V1aR, V1bR, and OTR
genes in specific brain regions suggest that these three gene products
may be independently regulated. Moreover, their expression in
structures including the hippocampus, arcuate and suprachiasmatic
nuclei, may suggest alternative interpretations of some radioreceptor
binding data and pharmacological effects observed after local
application of AVP and other selective agonists and antagonists
directly to brain (24, 25).
An interesting observation (See Table 1
) was that most brain regions
that expressed V1bR signal also expressed OTR transcripts. This is
intriguing considering that V1bR mRNA was extremely restricted in its
distribution, in that the majority of discrete brain regions do not
express the V1bR gene. The coexpression of OTR in virtually all
V1bR-labeled regions suggests that there may be a physiological basis
for their coexistence.
V1bR mRNA and AVP-immunoreactive pathways
AVP immunoreactive cells or processes have been reported in most
regions where we detect V1bR mRNA. AVP and OT secreting cells originate
primarily in the SON and PVN and project to the neural lobe of the
pituitary where the hormones are released directly into the
bloodstream. Central AVP projections originate from AVP-synthesizing
parvocellular neurons in the hypothalamic PVN, a few magnocellular
neurons in the SON, the bed nucleus of the stria terminalis (BNST), the
dorsomedial hypothalamus (DMH), medial amgydala, suprachiasmatic
nucleus (SCN), and locus coeruleus (26).
V1bR mRNA was not visualized in magnocellular or parvocellular neurons
in the PVN. The V1bR, therefore, is an unlikely candidate for directly
regulating AVP or OT release from PVN neurons. In contrast, both OTR
and V1aR (6) mRNAs were found in the PVN; the OTR mRNA was detected
throughout the PVN, whereas V1aR transcripts were localized primarily
in the parvocellular region. This distribution is consistent with a
role for OTR in the regulation of AVP release from the PVN.
OT-containing cells in the SON project to the posterior pituitary and
are well established to play a role in milk ejection during lactation
(27, 28). The SON expressed both V1bR and OTR transcripts (but not
V1aR, 6). Afferents include noradrenergic projections from the
ventrolateral medulla (29) and smaller projections from the median
preoptic nucleus, BNST and dorsomedial hypothalamic nucleus (30), the
latter two of which contain AVP-synthesizing neurons. The expression of
V1bR and OTR transcripts in the SON raises the possibility that the
V1bR and/or the OTR may be involved in regulating OT or AVP
release.
The differential localization of OTR mRNA with V1bR transcripts in the
SON and with V1aR gene products in the PVN raises interesting
possibilities regarding regulation and cross-talk in AVP- and
OT-containing brain systems. Experimental data narrowing the possible
interactions (e.g. V1b autoreceptor function; mediation of
selective effects on AVP or OT transcription or release; regulation of
OTR gene expression, etc.) await more precise colocalization
data and physiological experiments using highly selective receptor
subtype agonists and antagonists. Clearly, the selective localization
of V1aR and V1bR transcripts in the PVN and SON, respectively, could
function to provide a high degree of specificity in the cellular
responses to brain AVP in these magnocellular nuclei.
V1bR, OTR (shown here), and V1aR (6) transcripts were expressed by
cells in the SCN, where AVP-producing neurons have also been described
(31, 32). The SCN plays a role in circadian rhythmicity in hormone
secretions (33), body temperature (34); and sleep and waking cycles
(35). AVP exhibits a rhythmic pattern of secretion, with highest
levels during light periods and lowest levels during dark periods (36).
The V1aR mRNA in the SCN also exhibits a circadian rhythm but it is
12 h out of phase with AVP secretion and is independent of AVP
levels (37).
AVP is synthesized in the locus coeruleus and the DMH (26), two regions
that also express V1bR transcripts. The BNST, while a source of AVP,
does not express V1bR mRNA. Other areas where AVP immunoreactive
processes and V1bR mRNA have been found include the olfactory bulb,
arcuate nucleus of the hypothalamus, ventral tegmental area,
hippocampus, and substantia nigra pars compacta.
Overlap of V1bR with other AVP/OT receptors
The V1a receptor has been thought to mediate most of the effects
of AVP in brain (8, 9, 38, 39, 40, 41). The finding that a number of brain
regions express V1aR, V1bR and OTR mRNAs suggests that some of AVPs
effects on memory and learning (42), antipyresis (43), selective
aggression and partner preference (44, 45), cardiovascular responsivity
(46), blood flow to the choroid plexus and cerebrospinal fluid
production (47), smooth muscle tone in superficial brain vasculature
(48), and analgesia (49) may involve multiple receptor subtypes. All
three subtypes are expressed in the hippocampus (Fields of Ammons
horn), arcuate nucleus, locus coeruleus, substantia nigra pars
compacta, ventral tegmental area, suprachiasmatic nucleus, dorsal motor
nucleus of the vagus, and piriform cortex. Other regions, such as the
olfactory bulb and the hypothalamus express all three transcripts but
in markedly different patterns suggesting discrete functions for each
receptor subtype. The possibility that single cells coexpress all three
receptor genes remains to be determined. Some brain regions such as the
suprachiasmatic nucleus, piriform cortex (V1a, V1b, OTR), and the
supraoptic nucleus (V1b, OTR) appear to be likely candidates for
coexpression based on the large numbers of cells that label with each
respective hybridization probe.
Role for V1bR in brain
To date, the only function attributed to the V1bR has been the
potentiation of CRH induction of ACTH release in the pituitary (11, 12), and it is possible that V1bR may interact with CRH receptors at
other sites in brain. Several regions that are involved in processing
olfactory signals express both CRH receptors (50) and V1bR mRNA such as
the olfactory bulb (external plexiform layer), amygdala (PLCo, PMCo,
APir, AA), medial preoptic area, cortex (somatosensory, striate,
entorhinal, piriform), and pons. A role for V1bR in autonomic
regulation is suggested by its presence in hindbrain regions, some of
which are involved in cardiovascular function. V1bR transcripts were
detected in the facial nucleus, lateral reticular nucleus, the dorsal
motor nucleus of the vagus (DMV), the nucleus of the solitary tract
(NTS) and the trigeminal nucleus, areas important in AVPs and CRHs
autonomic effects, including those on heart rate, mean arterial blood
pressure, and plasma concentrations of epinephrine, norepinephrine,
glucose, and glucagon (46, 51). V1bR transcripts were in cells of the
locus coeruleus (LC) where AVP and norepinephrine may be colocalized
(52) and where vasopressinergic neurons may be involved in adaptation
to repeated stress (53). V1bR mRNA was also detected at low levels in
the dopamine-synthesizing regions of the substantia nigra par compacta
and ventral tegmental area. The coexpression of V1bR and OTR in many
brain regions suggests that the V1bR may play an interactive role with
OT receptive brain systems, possibly up- or down-regulating them in
conjunction with AVP release in specific pathways.
Distribution of OTR mRNA in CNS
We detected OTR transcripts in virtually all brain regions where
Yoshimura et al. (15) reported hybridization signal using
the human OTR-derived riboprobe (54). In contrast to their study, we
also visualized OTR transcripts in the suprachiasmatic nucleus and
portions of the inferior olivary nucleus. Whereas they described OTR
transcripts dorsal to the substantia nigra pars compacta, we visualized
signal throughout the medial pars compacta and ventral tegmental area.
Finally, we found OTR transcripts throughout the PVN whereas Yoshimura
and collaborators detected signal only over magnocells in the
dorso-medial portion. The subtle nature of the differences between our
results and those of Yoshimura et al. (15) suggest that they
may be attributable to the plane of section of tissue, gender or strain
differences. Overall, the degree of correspondence, rather than the
divergence, is noteworthy.
In summary, in situ hybridization data indicate that the
V1bR mRNA is expressed in a restricted number of morphologically
discrete brain regions. Regions expressing the highest levels of V1bR
transcripts also expressed OTR mRNA although the pattern of OTR gene
expression was far more extensive than that of V1bR. Both transcripts,
however, were more abundant in forebrain and hypothalamus than mid- and
hindbrain. The differential distributions of the genes encoding the
vasopressin V1a, V1b, and OT receptors confirm that these receptor
subtypes are distinct gene products and suggest that permutations in
their regional coexpression is may influence brain region-specific
regulation and functions. It remains to be determined whether V1aR,
V1bR, and OTR transcripts colocalize in individual cells. The
respective roles for these receptor subtypes in influencing cellular
activity and their potential for receptor subtype interactions at the
physiological level require further
investigation.2
 |
Acknowledgments
|
|---|
Thanks are extended to Elena Gournelos for her technical
assistance, Ricardo Dreifuss for his expert photographic work, and to
Drs. Agu Pert and Robert Post for their sponsorship of this project.
Appreciation is extended to C. S. Carter for her support and
encouragement.
 |
Footnotes
|
|---|
1 Portions of the OTR mRNA distribution data were presented at the
Wenner-Gren Conference, Stockholm, Sweden, 1996. This work was funded
by the NIMH, NIH and by grant no. MH-01050 to C. S. Carter that
provided partial support to C. Vaccari and E. Gournelos, who were also
recipients of Howard Hughes Undergraduate Fellowships from the
University of Maryland, College Park. 
2 The sequences of the V1b and OT receptor genes
can be obtained from S.J.L. upon request. 
Received July 30, 1998.
 |
References
|
|---|
-
Butlen D, Guillon G, Rajerison RM, Jard S, Sawyer
WH, Manning M 1978 Structural requirements for activation of
vasopressin-sensitive adenylate cyclase, hormone binding and
antidiuretic actions: effects of highly potent analogues and
competitive inhibitors. Mol Pharmacol 14:10061017[Abstract/Free Full Text]
-
Tribollet E, Barberis C, Dreifuss J-J, Jard S 1988 Autoradiographic localization of vasopressin and oxytocin binding sites
in rat kidney. Kidney Int 33:959965[Medline]
-
Ostrowski NL, Lolait SJ, Bradley DJ, OCarroll A-M,
Brownstein MJ, Young III WS 1992 Distribution of V1a and V2
vasopressin receptor messenger ribonucleic acids in rat liver, kidney,
pituitary, and brain. Endocrinology 131:533535[Abstract]
-
Michell RH, Kirk CJ, Billah MM 1979 Hormonal
stimulation of phosphatidylinosital breakdown, with particular
reference to the hepatic effects of vasopressin. Biochem Soc Trans 7:861865[Medline]
-
Morel A, OCarroll A-M, Brownstein MJ, Lolait SJ 1992 Molecular cloning and expression of a rat V1a arginine vasopressin
receptor. Nature 356:523526[CrossRef][Medline]
-
Ostrowski NL, Lolait SJ, Young III WS 1994 Cellular localization of vasopressin V1a receptor messenger ribonucleic
acid in adult male rat brain, pineal, and brain vasculature.
Endocrinology 135:15111528[Abstract]
-
Ostrowski NL, Young III WS, Knepper MA, Lolait SJ 1993 Expression of vasopressin V1a and V2 receptor messenger
ribonucleic acid in liver and kidney of embryonic, developing, and
adult rats. Endocrinology 133:18491859[Abstract]
-
Barberis C, Tribollet E 1996 Vasopressin and
oxytocin receptors in the central nervous system. Crit Rev Neurobiol 10:119154[Medline]
-
Kremarik P, Freund-Mercier M-J, Stoeckel M-E 1993 Histoautoradiographic detection of oxytocin- and vasopressin-binding
sites in the telencephalon of the rat. J Comp Neurol 333:343359[CrossRef][Medline]
-
Gerstberger R, Fahrenholz F 1989 Autoradiographic
localization of V1 vasopressin binding sites in rat brain and kidney.
Eur J Pharmacol 167:105116[CrossRef][Medline]
-
Antoni FA 1984 Novel ligand specificity of
pituitary vasopressin receptors in the rat. Neuroendocrinology
39:186188, 512:195204
-
Antoni FA 1993 Vasopressinergic control of the
pituitary adrenocorticotropin secretion comes of age. Front
Neuroendocrinol 14:76122[CrossRef][Medline]
-
Lolait SJ, OCarroll A-M, McBride OW, Konig M, Morel A,
Brownstein MJ 1995 Extrapituitary expression of the rat V1b
vasopressin receptor gene. Proc Natl Acad Sci USA 92:67836787[Abstract/Free Full Text]
-
Saito M, Sugimoto T, Tahara A, Kawashima H 1995 Molecular cloning and characterization of rat V1b vasopressin receptor:
evidence for its expression in extrapituitary tissues. Biochem Biophys
Res Commun 212:751757[CrossRef][Medline]
-
Yoshimura R, Kiyama H, Kimura T, Araki T, Maeno H,
Tanizawa O, Tohyama M 1993 Localization of oxytocin receptor
messenger ribonucleic acid in the rat brain. Endocrinology 133:12391246[Abstract]
-
Ostrowski NL, Young, III WS, Lolait SJ 1995 Estrogen increases renal oxytocin receptor gene expression.
Endocrinology 136:18011804[Abstract]
-
Paxinos G, Watson C 1986 The Rat Brain in
Stereotaxic Coordinates, Ed. 2. Academic Press, Orlando
-
Freund-Mercier MJ, Stoeckel ME, Palacios JM, Pazos A,
Reichhart JM, Porte A, Richard P 1987 Pharmalogical
characteristics and anatomical distribution of [3H]oxytocin-binding
sites in the wastar rat studies by autoradiography. Neuroscience 20:599614[CrossRef][Medline]
-
Johnson AE, Audigier S, Rossi F, Jard S, Tribollet E,
Barberis C 1993 Localization and characterization of vasopressin
binding sites in the rat brain using iodinated linear AVP antagonist.
Brain Res 622:916[CrossRef][Medline]
-
Tribollet E, Goumaz M, Raggenbass M, Dubois-Dauphin M,
Dreifuss JJ 1991 Early appearance and transient expression of
vasopressin receptors in the brain of rat fetus and infant. An
autoradiographical and electrophysiological study. Dev Brain Research 58:1324
-
Lolait SJ, OCarroll A-M, McBride OW, Konig M, Morel A,
Brownstein MJ 1992 Cloning and characterization of a vasopressin
V2 receptor and possible link to nephrogenic diabetes insipidus. Nature 357:336339[CrossRef][Medline]
-
Jeng Y-J, Lolait, SJ, Strakova Z, Chen C, Copland JA,
Mellman O, Hellmich MR, Soloff MS 1996 Molecular cloning and
functional characterization of the oxytocin receptor from a rat
pancreatic cell line (RINmSF). Neuropeptides 30:557565[CrossRef][Medline]
-
Kato Y, Igarashi N, Hirasawa A, Tsujimoto G,
Kobayashi 1995 Distribution and developmental changes in
vasopressin V2 receptor mRNA in rat brain. Differentiation 59:163169[CrossRef][Medline]
-
Kubota M, Landgraf R, Wotjak CT 1996 Release of
vasopressin within the rat suprachiasmatic nucleus: no effect of a
V1/V2 antagonist. Neuroreport 7:19331936[Medline]
-
Tribollet E 1992 Vasopressin and oxytocin receptors
in the rat brain. In: Bjorklund A, Hokfelt T and Kuhar MJ (eds)
Handbook of Chemical Neuroanatomy. Vol 11: Neuropeptide Receptors in
the CNS, Elsevier, pp 289320
-
De Vries GJ, Buijs RM, Van Leeuwen FW, Caffe AR, Swaab
DF 1985 The vasopressinergic innervation of the brain in normal
and castrated rats. J Comp Neurol 233:236254[CrossRef][Medline]
-
Bissett GW 1974 Milk ejections. In: Knobil E,
Sawyer WH (eds) Handbook of Physiology, Sect 7: Endocrinology vol IV,
part I. The Pituitary Gland and its Neuroendocrine Control. American
Physiological Association, Washington, DC; pp 493520.
-
Hatton GI, Modney BK, Salm AK 1992 Increases in
dendritic bundling and dye coupling of supraoptic neurons after the
induction of maternal behavior. Ann NY Acad Sci 652:142155[CrossRef][Medline]
-
Sawchenko PE, Swanson LW 1982 The organization of
noradrenergic pathways from the brainstem to the paraventricular and
supraoptic nuclei in the rat. Brain Res Rev 4:275325
-
Sawchenko PE, Swanson LW 1983 The organization of
forebrain afferents to the paraventricular and supraoptic nuclei of the
rat. J Comp Neurol 218:121144[CrossRef][Medline]
-
Swaab DF, Pool CW 1975 Specificity of oxytocin and
vasopressin immunofluorescence. J Endocrinol 66:263272[Abstract/Free Full Text]
-
Vandesande F, Dierickx K, De Mey J 1975 Identification of the vasopressin-neurophysin producing neurons of the
rat suprachiasmatic nuclei. Cell Tissue Res 36:195215
-
Moore RY, Eichler VB 1972 Loss of circadian adrenal
corticosterone rhythm following suprachiasmatic lesions. Brain Res 42:201206[CrossRef][Medline]
-
Refinetti R 1995 Effects of suprachiasmatic lesions
on temperature regulation in the golden hamster. Brain Res Bull 36:8184[CrossRef][Medline]
-
Ibuka N, Kawamura H 1975 Loss of circadian rhythm
in sleep-wakefulness cycle in the rat by suprachiasmatic nucleus
lesions. Brain Res 96:7681[CrossRef][Medline]
-
Earnest DJ, Sladek CD 1986 Circadian rhythms of
vasopressin release from individual rat suprachiasmatic explants in
vitro. Brain Res 382:129133[CrossRef][Medline]
-
Young III WS, Kovacs K, Lolait SJ 1993 The diurnal
rhythm of vasopressin V1a receptor expression in the suprachiamatic
nucleus is not dependent on vasopressin. Endocrinology 133:585590[Abstract]
-
Buijs RM, Swaab DF 1979 Immunoelectron
microscopical demonstration of vasopressin and oxytocin in the limbic
system of the rat. Cell Tissue Res 204:355365[Medline]
-
Buijs RM, Van Heerikhuize JJ 1982 Vasopressin and
oxytocin release in the brain: a synaptic event. Brain Res 252:7176[CrossRef][Medline]
-
Joels M, Urban IJA 1982 The effect of
microiontophoretically applied vasopressin and oxytocin on single
neurones in the septum and dorsal hippocampus of the rat. Neurosci Lett 33:7984[CrossRef][Medline]
-
Van Leeuwen FW, Wolters P 1983 Light microscopic
autoradiographic localization of 3H-arginine vasopressin binding sites
in the rat brain and kidney. Neurosci Lett 41:6166[CrossRef][Medline]
-
Moratella R, Borrell J, Sanchez-Franco F, del Rio J 1987 Neonatal administration of vasopressin antiserum induces long-term
deficits on active and passive avoidance behavior in rats. Behav Brain
Res 23:231237[CrossRef][Medline]
-
Bock M, Roth J, Kluger MJ, Zeisberger E 1994 Antipyresis caused by stimulation of vasopressinergic neurons and
intraseptal or systemic infusions of gamma-MSH. Am J Physiol
266:R614R621
-
Carter CS, Williams JR, Witt DM, Insel TR 1992 Oxytocin and social bonding. Ann NY Acad Sciences 652:204211[Medline]
-
Winslow JT, Hastings N, Carter CS, Harbaugh CR, Insel
TR 1993 A role for central vasopressin in pair bonding in
monogamous prairie voles. Nature 365:545548[CrossRef][Medline]
-
Berecek KH 1991 Role of vasopressin in central
cardiovascular regulation. In: Kunos G, Ciriello J (eds) Central Neural
Mechanisms in Cardiovascular Regulation. Boston, Birkhauser, 2:134
-
Faraci FM, Mayhan WG, Farrell WJ, Heistad DD 1988 Humoral regulation of blood flow to choroid plexus: role of arginine
vasopressin. Circ Res 63:373379[Abstract/Free Full Text]
-
Katusic ZS, Shepard JT, Vanhoutte PM 1984 Vasopressin causes endothelium-dependent relaxations of the canine
basilar artery. Circ Res 55:575579[Abstract/Free Full Text]
-
Oluyomi AO, Hart SL 1992 Antinociceptive and
thermoregulatory actions of vasopressin are sensitive to a V1-receptor
antagonist. Neuropeptides 23:137142[CrossRef][Medline]
-
De Souza EB 1987 Corticotropin-releasing factor
receptors in the rat central nervous system: characterization and
regional distribution. J Neuroscience 7:88100[Abstract]
-
Rascher W, Lang RE, Unger T 1985 Vasopressin,
cardiovascular regulation and hypertension. In: Ganten D, Pfaff D (eds)
Neurobiology of Vasopressin. Berlin, Springer-Verlag, pp 101136
-
Caffe AR, van Leeuwen FW, Buijs RM, de Vries GJ, Geffard
M 1985 Coexistence of vasopressin, neurophysin and noradrenaline
in the locus coeruleus and subcoeruleus in the rat. Brain Res 338:160164[CrossRef][Medline]
-
Chen X, Herbert J 1995 Alterations in sensitivity
to intracerebral vasopressin and the effects of a V1a receptor
antagonist on cellular, autonomic and endocrine responses to repeated
stress. Neuroscience 64:687697[CrossRef][Medline]
-
Ostrowski NL Oxytocin receptor messenger
ribonucleic acid expression in rat brain: implications for behavioral
integration. Psychoneuroendocrinology, in pressAU: Your
manuscript was edited by hand because the editorial office did not send
us a disk.AU: Correct reference?AU: Please list
name and location of each manufacturer at first use.AU:
Reference 20 needs to be cited in order here or deleted in
proof.AU: Is this the correct reference no?AU:
This footnote needs to be cited in order in text.AU: Name of
organization as meant?AU: See note about this reference in
text.AU: Journal title? If 1997, hasnt it been published
by now? If so, please provide complete vol #, page numbers.
This article has been cited by other articles:

|
 |

|
 |
 
A. Pena, B. Murat, M. Trueba, M. A. Ventura, G. Bertrand, L. L. Cheng, S. Stoev, H. H. Szeto, N. Wo, G. Brossard, et al.
Pharmacological and Physiological Characterization of d[Leu4, Lys8]Vasopressin, the First V1b-Selective Agonist for Rat Vasopressin/Oxytocin Receptors
Endocrinology,
September 1, 2007;
148(9):
4136 - 4146.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. S.-L. Gal, D. Raufaste, S. Derick, J. Blankenstein, J. Allen, B. Pouzet, M. Pascal, J. Wagnon, and M. A. Ventura
Biological characterization of rodent and human vasopressin V1b receptors using SSR-149415, a nonpeptide V1b receptor ligand
Am J Physiol Regulatory Integrative Comp Physiol,
August 1, 2007;
293(2):
R938 - R949.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. E. Blevins, M. W. Schwartz, and D. G. Baskin
Evidence that paraventricular nucleus oxytocin neurons link hypothalamic leptin action to caudal brain stem nuclei controlling meal size
Am J Physiol Regulatory Integrative Comp Physiol,
July 1, 2004;
287(1):
R87 - R96.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S. Oshikawa, A. Tanoue, T.-a. Koshimizu, Y. Kitagawa, and G. Tsujimoto
Vasopressin Stimulates Insulin Release from Islet Cells through V1b Receptors: a Combined Pharmacological/Knockout Approach
Mol. Pharmacol.,
March 1, 2004;
65(3):
623 - 629.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
G. Griebel, J. Simiand, C. Serradeil-Le Gal, J. Wagnon, M. Pascal, B. Scatton, J.-P. Maffrand, and P. Soubrie
Anxiolytic- and antidepressant-like effects of the non-peptide vasopressin V1b receptor antagonist, SSR149415, suggest an innovative approach for the treatment of stress-related disorders
PNAS,
April 30, 2002;
99(9):
6370 - 6375.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
C. S.-L. Gal, J. Wagnon, J. Simiand, G. Griebel, C. Lacour, G. Guillon, C. Barberis, G. Brossard, P. Soubrie, D. Nisato, et al.
Characterization of (2S,4R)-1-[5-Chloro-1-[(2,4-dimethoxyphenyl)sulfonyl]-3-(2-methoxy-phenyl)-2-oxo-2,3-dihydro-1H-indol-3-yl]-4-hydroxy-N,N-dimethyl-2-pyrrolidine carboxamide (SSR149415), a Selective and Orally Active Vasopressin V1b Receptor Antagonist
J. Pharmacol. Exp. Ther.,
March 1, 2002;
300(3):
1122 - 1130.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
S.-S. Cui, R. C. Bowen, G.-B. Gu, D. K. Hannesson, P. H. Yu, and X. Zhang
Prevention of Cannabinoid Withdrawal Syndrome by Lithium: Involvement of Oxytocinergic Neuronal Activation
J. Neurosci.,
December 15, 2001;
21(24):
9867 - 9876.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
J. P. H. Burbach, S. M. Luckman, D. Murphy, and H. Gainer
Gene Regulation in the Magnocellular Hypothalamo-Neurohypophysial System
Physiol Rev,
July  |