| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
ARTICLES |
Department of Anatomy (E.H., I.K., T.H., Zs.L.), Albert Szent-Györgyi Medical University, 6724 Szeged, Hungary; and The Women’s Health Research Institute (P.S., I.M.), Wyeth-Ayerst Research, Radnor, Pennsylvania 19087
Address all correspondence and requests for reprints to: Istvan Merchenthaler, M.D., D.Sc., Women’s Health Research Institute, Wyeth-Ayerst Research, 1456 King of Prussia Road, Radnor, Pennsylvania 19087. E-mail: merchei{at}war.wyeth.com
 |
Abstract |
|---|
 Top Abstract IntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
) in the
PVN and the SON of the rat. The present experiments using a combined
ICC and ISH method were undertaken to examine the expression of the
recently cloned beta form of ER (ER-ß) in OT- and VP-immunoreactive
(IR) neuronal systems of the rat hypothalamus. The results demonstrate
that the highest cellular levels of ER-ß messenger RNA (mRNA) in
OT-IR neurons can be visualized in the caudal portion of the PVN and in
an area ventro-medial to the central core of VP-IR cells. These neurons
were previously shown to project caudally to the brain stem and the
spinal cord to regulate autonomic functions. In addition, the whole
rostro-caudal extent of the PVN and the SON contained OT-IR neurons
that coexpressed variable levels of ER-ß mRNA. Similarly, the
presence of ER-ß mRNA was seen in a large population of VP-IR
paraventricular and supraoptic neurons. In the SON, somewhat stronger
hybridization signal was detected in VP-IR neurons as compared with
OT-IR neurons. Together, these findings provide strong support for the concept that the functions of OT- and VP-IR neurons in the PVN and the SON are regulated directly by estrogen and that the genomic effects of estrogens are mediated by ER-ß.
|
Introduction |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Recently, a new estrogen receptor, termed ER-ß, was cloned from the rat prostate gland (16). In situ hybridization studies with ER-ß-specific complementary RNA (cRNA) probes have established a wide distribution of ER-ß mRNA in the hypothalamus (17) and brain (18) of the rat. One interesting finding of these experiments was the high level of ER-ß mRNA in the PVN and the SON. The aim of the present studies was to analyze the expression of ER-ß mRNA in OT- and VP-IR neurons of the hypothalamic PVN and SON, by means of a combined ICC and ISH method (19).
|
Materials and Methods |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
ISH detection of ER-ß mRNA by autoradiography
For single-labeling ISH studies of ER-ß mRNA expression,
fresh-frozen sections including the hypothalamic PVN and SON of the
ovariectomized female rat were used as described earlier (18). For
single-cell analysis of the hybridization signal, the autoradiograms
were visualized on Kodak NTB-3 photograhic emulsion.
Combined use of ICC and ISH in the same sections
The methodology of combined ICC and ISH was modified from a
previous protocol (19).
Animals
Five female Wistar rats (200–220 g) were maintained in a
controlled environment (5-h light, 19-h dark, 22 C), with food and
water available ad libitum. The animals were anesthetized
with Avertin (1 ml/100 g BW), and gonadectomized bilaterally. On
postovariectomy day 12, the animals were anesthetized and killed by
transcardiac perfusion using a short flush with 0.1 M PBS
(pH 7.6), followed by 400 ml of a 4% paraformaldehyde solution in PBS.
Small tissue blocks containing the hypothalamic SON and PVN were
dissected from the brains, infiltrated with gradually increasing
concentrations of sucrose through 30% (for 24 h total), and
snap-frozen on dry-ice. Then, 20 µm coronal sections were prepared on
a freezing microtome (Reichert-Jung), collected and stored in a
cryoprotectant solution at -20 C (20) until use.
Preincubation, hybridization, and washes
Immediately before hybridization, the sections were removed from
the cryoprotectant solution and rinsed thoroughly in 2 x standard
saline citrate solution (2 x SSC; 1 x SSC = 0.15
M NaCl/0.015 M sodium citrate, pH 7.0).
Subsequently, they were pretreated with proteinase K (Serva
Feinbiochemica GmbH & Co., Heidelberg, Germany; 1 µg/ml, dissolved in
2 x SSC at room temperature) for 30 min, postfixed with 4%
paraformaldehyde for 5 min to stop the digestion, rinsed shortly in
2 x SSC, and acetylated with 0.25% acetic anhydride in 0.1
M triethanolamine (pH 8.0)/0.9% NaCl for 20 min. Finally,
the sections were rinsed in 2 x SSC and transferred into
hybridization solution.
During the hybridization, the sections were incubated in microcentrifuge tubes containing the hybridization cocktail [50% formamide, 4 x SSC, 10% dextran sulfate (500,000 mol wt; Sigma Chemical Co., St. Louis, MO), 1 x Denhardt’s solution, 500 µg/ml heparin sodium salt (Sigma), 0.5 mg/ml yeast tRNA (Boehringer Mannheim GmbH, Mannheim, Germany), 0.4 mg/ml sheared single-stranded salmon sperm DNA (Boehringer Mannheim GmbH), 200 mM dithiothreitol, and 30,000 cpm/µl of each hybridization probe. The tubes were sealed with Parafilm to exclude atmospheric air and placed in an incubator for hybridization overnight at 52 C.
In the morning, the hybridized sections were rinsed in 1 x SSC for 10 min, followed by a 1-h stringency wash in 50% formamide/2 x SSC at 50 C and a 1-h digestion of excess hybridization probes with RNAse A (Boehringer Mannheim GmbH; 100 µg/ml in 2 x SSC buffer) at 37 C. Finally, two sequential stringent treatment steps (1 h each) were performed in 50% formamide/2 x SSC solutions at 50 C and the sections were rinsed in 0.1 M PBS with 0.2% Triton X-100.
Immunocytochemical detection of oxytocin and vasopressin
Before the immunocytochemical detection of either OT or VP was
carried out, the sections were immersed in 0.5%
H2O2 in PBS for 10 min and blocked with 2% BSA
against nonspecific antibody-binding for 20 min. The primary monoclonal
antibodies for neurophysin-OT (PS-38; 1/1000, kindly provided by Dr.
Sharon Key, Public Health Service, NIH, Bethesda, MD) were diluted with
2% BSA in PBS and applied to the sections for 12 h at 4 C. The
tissue-bound antibodies were reacted with biotinylated antimouse IgG
(1/800; Jackson ImmunoResearch Laboratories, Inc., West Grove, PA),
then with streptavidin-peroxidase complex (1/2000; Jackson
ImmunoResearch Laboratories, Inc.) for 1 h each. The antiserum
against VP (Incstar Corp., Stillwater, MN) was raised in a rabbit and
applied to the sections at a 1/4000 working dilution for 12 h. The
detection protocol included sequential incubation of sections in the
antirabbit IgG (1/500, Arnel Products Co., Inc., New York, NY) and
then, in the peroxidase-antiperoxidase complex (1/2000, Dako
Corporation, Carpinteria, CA) solutions for 1 h each. Finally, OT-
and VP-IR neurons were visualized in a developer containing 0.01%
diaminobenzidine tetrahydrochloride (DAB; Sigma-Aldrich Chemical
Company) and 0.003% H2O2 in 0.1 M
Tris-HCl buffer (pH 7.6).
Detection of the hybridization signal
The immunostained sections were rinsed in PBS for 5 min,
transferred briefly into 0.3% Elvanol with 300 mM ammonium
acetate, mounted onto precleaned double gelatin-coated microscopic
slides, and air-dried. They were then dehydrated in a graded series of
ethanol through 100%, dried, and then dipped into photographic
emulsion (LM-1; Amersham International plc, Amersham, UK) and exposed
for 3–6 weeks at 4 C. The slide autoradiograms were developed with
Kodak D19 developer for 3 min, rinsed briefly with distilled water,
then fixed with Kodak fixer for 5 min. Finally, the sections were
dehydrated in ethanols, cleared in xylenes and coverslipped with
Permount.
Mapping of double-labeled cells
The immunocytochemical distribution of OT- and VP-IR neurons did
not seem to respect the borders of the classical anatomical subnuclei
of the PVN. Moreover, a high percent of OT-IR neurons occurred in the
classical parvocellular subnuclei of the PVN (21). Therefore, the
topographical analysis of double- and single-labeled neurons in the PVN
followed a simplified terminology adapted from a previous
immunocytochemical study of OT- and VP-IR neurons, which subdivided the
PVN into a rostral (rPVN) a middle (mPVN) and a caudal (cPVN) portion
(22).
In the caudal portion of the PVN, where the highest cellular levels of ER-ß mRNA were detected, a semiquantitative estimate of the numbers of ER-ß-positive OT-IR neurons was made. From sixteen sections representing the cPVN of four animals, a total of 543 OT-IR neurons were analyzed for co-expression of ER-ß mRNA.
|
Results |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
), then in the mPVN (Fig. 1b) and
finally, in the rPVN (not shown) and the SON (Fig. 1c). In the SON, the
signal had a tendency to be slightly higher in the ventral than in the
dorsal part of the nucleus.
|
).
|
, a and b). Semiquantitative analysis of OT neurons further
revealed that 93 ± 6.8% also expressed ER-ß hybridization
signal. In addition, the few VP-IR neurons that intermingled with OT
neurons in the cPVN often coexpressed detectable, albeit relatively
lower levels of ER-ß mRNA. In the mPVN, the strongest hybridization
signal was detected in cells situated ventro-medial to the central core
of VP neurons, and dual-labeling studies with the OT antiserum have
established that most of them were OT-ergic. Variable levels of ER-ß
mRNA were revealed in different populations of OT- as well as VP-IR
(Fig. 2c) neurons. Subsets of OT- and VP-IR neurons in the mPVN did not
contain detectable hybridization signal. Similarly, the population of
OT-IR neurons in the rPVN consisted of a mixture of ER-ß
mRNA-expressing and ER-ß mRNA-negative neurons, reflecting either
lack of ER-ß-coexpression in some OT-ergic neurons or a limitation
of the method.
Supraoptic nucleus
In the SON, ER-ß mRNA was coexpressed both in VP- (Fig. 2, d and
e) and OT-IR (Fig. 2f) neurons. Somewhat higher cellular levels of the
receptor mRNA were seen in VP as compared with OT neurons. Dual-labeled
cells appeared along the rostro-caudal extent of the nucleus. A longer
exposure time was needed to visualize the hybridization signal in the
SON, compared with the PVN.
|
Discussion |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
Substantial data support an important role for estrogen in the
regulation of magnocellular OT and VP neurons. The concentration of OT
in the pituitary (9) and the hypophyseal portal blood (23) as well as
OT mRNA levels in the SON (9) change throughout the estrus cycle and
estrogen treatment of ovariectomized rats increases plasma OT levels
(24). In addition, VP mRNA in the SON is elevated in lactating and
pregnant rats (9), and lactation also increases the percent ratio of OT
neurons that coexpress VP mRNA in this nucleus (25). The effects of
estrogen on the magnocellular systems are well documented, although
whether they are direct or interneuron-mediated have long been a
question of controversy. In the guinea pig, most OT neurons of the PVN
and the SON contain immunoreactive ER (10), supporting the hypothesis
of a direct effect of estrogen. In contrast, few magnocellular neurons
were found to contain ER immunoreactivity in sheep (26) and monkeys
(27). In rats, only a restricted population of paraventricular neurons
concentrate tritiated estradiol (11, 12, 13). In situ
hybridization histochemical studies of the rat hypothalamus have
revealed the absence of ER- mRNA in the SON and PVN (18). Therefore,
the concept that the actions of estrogen on OT and VP neurons are
mediated by estrogen-sensitive interneurons has been raised.
Accordingly, an ER-IR GABA interneuron population located in the
perinuclear zone of the SON has been implicated in the circuitry,
whereby estrogens might regulate OT neurons of the SON (14).
Recently, a second form of ER, termed ER-ß, has been cloned from rat
prostate (16). Using ISH with complementary probes to the ER-ß mRNA,
the anatomical distribution of ER-ß mRNA-expressing cells has been
mapped in the hypothalamus (17) and brain (18) of the rat. A surprising
observation of these studies was the wide distribution of ER-ß mRNA
in the PVN and the SON. We now show that a large percent of OT- and
VP-IR neurons in these nuclei coexpresses ER-ß mRNA. The highest
hybridization signal was revealed in the cPVN, where 93 ± 6.8%
of OT-IR neurons expressed detectable levels of ER-ß mRNA.
Interestingly, this topographical distribution of double-labeled OT
neurons highly resembles the map of neurophysin-containing neurons that
exhibit nuclear uptake of tritiated estradiol (12, 13), and project
caudally to the medulla and/or spinal cord to influence autonomic
functions (21). Nevertheless, the area populated by ER-ß
mRNA-positive OT neurons is larger and includes the whole rostro-caudal
extent of the PVN as well as the SON, comprising regions that project
to the posterior lobe of the pituitary gland. Most VP-ergic neurons
expressing ER-ß mRNA were localized in the middle portion of the PVN
(mPVN) and ventrally in the SON. To establish the precise role of
ER-ß in functionally distinct subpopulations of OT and VP neurons and
to identify parvicellular neuropeptide systems that express ER-ß mRNA
in the subnuclei of the PVN, further studies will be required. The
genes regulated by ER-ß in OT and VP neurons are presently unclear.
However, identification of ER-ß mRNA in OT neurons, most of which do
not express ER-, might explain the presence of functional
estrogen-response elements on the promoter of the OT gene, itself (28).
Among the neuropeptides that have been colocalized in magnocellular VP
neurons (29), galanin might represent a putative target for regulation
by ER-ß because of the presence of estrogen-response elements on the
preprogalanin gene (30).
The method of combined ICC and ISH has been used successfully earlier for the colocalization of preprogalanin mRNA with c-Fos- and LHRH immunoreactivities in the preoptic area of the female rat (19). In the present application of the combination technique, several efforts have been made to maximize the sensitivity of the ISH detection component. This seemed to be especially important in view of the relatively low cellular abundance of ER-ß mRNA. Modifications we have introduced to the protocol included a proteinase K digestion step before hybridization to facilitate access of probes to the target mRNA and combination of two antisense hybridization probes in the hybridization cocktail, instead of using a single cRNA probe. These changes markedly increased the sensitivity of the hybridization.
In summary, the present studies have localized ER-ß mRNA in paraventricular and supraoptic OT-IR and VP-IR neurons of the rat. These new data suggest that estrogen directly regulates gene(s) in OT-IR and VP-IR neurons.
|
Acknowledgments |
|---|
|
Footnotes |
|---|
Received November 7, 1997.
|
References |
|---|
|
TopAbstractIntroductionMaterials and MethodsResultsDiscussionReferences |
|---|
and -ß mRNA in the
rat central nervous system. J Comp Neurol 388:507–525[CrossRef][Medline]
This article has been cited by other articles:
 |
|
 |
|
  M. Hayashi, H. Arima, N. Ozaki, Y. Morishita, M. Hiroi, N. Ozaki, H. Nagasaki, N. Kinoshita, M. Ueda, A. Shiota, et al. Progressive polyuria without vasopressin neuron loss in a mouse model for familial neurohypophysial diabetes insipidus Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2009; 296(5): R1641 - R1649. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 H. Sakamoto, K.-i. Matsuda, K. Hosokawa, M. Nishi, J. F. Morris, E. R. Prossnitz, and M. Kawata Expression of G Protein-Coupled Receptor-30, a G Protein-Coupled Membrane Estrogen Receptor, in Oxytocin Neurons of the Rat Paraventricular and Supraoptic Nuclei Endocrinology, December 1, 2007; 148(12): 5842 - 5850. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. D. Lund, L. R. Hinds, and R. J. Handa The Androgen 5{alpha}-Dihydrotestosterone and Its Metabolite 5{alpha}-Androstan-3beta, 17beta-Diol Inhibit the Hypothalamo-Pituitary-Adrenal Response to Stress by Acting through Estrogen Receptor beta-Expressing Neurons in the Hypothalamus J. Neurosci., February 1, 2006; 26(5): 1448 - 1456. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. T. Ghorbel, G. Sharman, C. Hindmarch, K. G. Becker, T. Barrett, and D. Murphy Microarray screening of suppression subtractive hybridization-PCR cDNA libraries identifies novel RNAs regulated by dehydration in the rat supraoptic nucleus Physiol Genomics, January 12, 2006; 24(2): 163 - 172. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A.-M. Bao, A. Hestiantoro, E. J. W. Van Someren, D. F. Swaab, and J.-N. Zhou Colocalization of corticotropin-releasing hormone and oestrogen receptor-{alpha} in the paraventricular nucleus of the hypothalamus in mood disorders Brain, June 1, 2005; 128(6): 1301 - 1313. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. J. Somponpun, A. K. Johnson, T. Beltz, and C. D. Sladek Estrogen receptor-{alpha} expression in osmosensitive elements of the lamina terminalis: regulation by hypertonicity Am J Physiol Regulatory Integrative Comp Physiol, September 1, 2004; 287(3): R661 - R669. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Suzuki and R. J. Handa Regulation of Estrogen Receptor-{beta} Expression in the Female Rat Hypothalamus: Differential Effects of Dexamethasone and Estradiol Endocrinology, August 1, 2004; 145(8): 3658 - 3670. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. J. Somponpun, A. K. Johnson, T. Beltz, and C. D. Sladek Osmotic regulation of estrogen receptor-{beta} expression in magnocellular vasopressin neurons requires lamina terminalis Am J Physiol Regulatory Integrative Comp Physiol, March 1, 2004; 286(3): R465 - R473. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. L. Rincavage, D. P. McDonnell, and C. M. Kuhn Expression of Functional Estrogen Receptor {beta} in Locus Coeruleus-Derived Cath.a Cells Endocrinology, July 1, 2003; 144(7): 2829 - 2835. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. J. Somponpun and C. D. Sladek Osmotic Regulation of Estrogen Receptor-{beta} in Rat Vasopressin and Oxytocin Neurons J. Neurosci., May 15, 2003; 23(10): 4261 - 4269. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E. Choleris, J.-A. Gustafsson, K. S. Korach, L. J. Muglia, D. W. Pfaff, and S. Ogawa An estrogen-dependent four-gene micronet regulating social recognition: A study with oxytocin and estrogen receptor-alpha and -beta knockout mice PNAS, May 13, 2003; 100(10): 6192 - 6197. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
B. Greco, L. S. Lubbers, and J. D. Blaustein Estrogen Receptor {beta} Messenger Ribonucleic Acid Expression in the Forebrain of Proestrous, Pregnant, and Lactating Female Rats Endocrinology, May 1, 2003; 144(5): 1869 - 1875. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Somponpun and C. D. Sladek Role of Estrogen Receptor-{beta} in Regulation of Vasopressin and Oxytocin Release in Vitro Endocrinology, August 1, 2002; 143(8): 2899 - 2904. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. B. Patisaul, M. Melby, P. L. Whitten, and L. J. Young Genistein Affects ER{beta}- But Not ER{alpha}-Dependent Gene Expression in the Hypothalamus Endocrinology, June 1, 2002; 143(6): 2189 - 2197. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Orikasa, Y. Kondo, S. Hayashi, B. S. McEwen, and Y. Sakuma Sexually dimorphic expression of estrogen receptor beta in the anteroventral periventricular nucleus of the rat preoptic area: Implication in luteinizing hormone surge PNAS, February 14, 2002; (2002) 52707299. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 B. McEwen Estrogen Actions Throughout the Brain Recent Prog. Horm. Res., January 1, 2002; 57(1): 357 - 384. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
H. B. Patisaul, M. Dindo, P. L. Whitten, and L. J. Young Soy Isoflavone Supplements Antagonize Reproductive Behavior and Estrogen Receptor {{alpha}}- and {beta}-Dependent Gene Expression in the Brain Endocrinology, July 1, 2001; 142(7): 2946 - 2952. [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 1, 2001; 81(3): 1197 - 1267. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 K. S. Bramlett, Y. Wu, and T. P. Burris Ligands Specify Coactivator Nuclear Receptor (NR) Box Affinity for Estrogen Receptor Subtypes Mol. Endocrinol., June 1, 2001; 15(6): 909 - 922. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 M. K. Österlund, J.-A. Gustafsson, E. Keller, and Y. L. Hurd Estrogen Receptor {beta} (ER{beta}) Messenger Ribonucleic Acid (mRNA) Expression within the Human Forebrain: Distinct Distribution Pattern to ER{alpha} mRNA J. Clin. Endocrinol. Metab., October 1, 2000; 85(10): 3840 - 3846. [Abstract] [Full Text]
|
|
|
|
|
|
T. A. Ishunina, F. P. M. Kruijver, R. Balesar, and D. F. Swaab Differential Expression of Estrogen Receptor {alpha} and {beta} Immunoreactivity in the Human Supraoptic Nucleus in Relation to Sex and Aging J. Clin. Endocrinol. Metab., September 1, 2000; 85(9): 3283 - 3291. [Abstract] [Full Text]
|
|
|
|
|
|
Vasopressin and Oxytocin Neurons of the Human Supraoptic and Paraventricular Nucleus; Size Changes in Relation to Age and Sex J. Clin. Endocrinol. Metab., December 1, 1999; 84(12): 4637 - 4644. [Abstract] [Full Text]
|
|
|
|
 |
|
 B. S. McEwen and S. E. Alves Estrogen Actions in the Central Nervous System Endocr. Rev., June 1, 1999; 20(3): 279 - 307. [Abstract] [Full Text]
|
|
|
|
|
|
B. S. McEwen The Molecular and Neuroanatomical Basis for Estrogen Effects in the Central Nervous System J. Clin. Endocrinol. Metab., June 1, 1999; 84(6): 1790 - 1797. [Full Text]
|
|
|
|
|
|
P. J. Shughrue, M. V. Lane, and I. Merchenthaler Biologically Active Estrogen Receptor-{beta}: Evidence from in Vivo Autoradiographic Studies with Estrogen Receptor {alpha}-Knockout Mice Endocrinology, June 1, 1999; 140(6): 2613 - 2620. [Abstract] [Full Text]
|
|
|
|
 |
|
 S. M. Hileman, R. J. Handa, and G. L. Jackson Distribution of Estrogen Receptor-ß Messenger Ribonucleic Acid in the Male Sheep Hypothalamus Biol Reprod, June 1, 1999; 60(6): 1279 - 1284. [Abstract] [Full Text]
|
|
|
|
|
|
J. A. McCracken, E. E. Custer, and J. C. Lamsa Luteolysis: A Neuroendocrine-Mediated Event Physiol Rev, April 1, 1999; 79(2): 263 - 323. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. Orikasa, Y. Kondo, S. Hayashi, B. S. McEwen, and Y. Sakuma Sexually dimorphic expression of estrogen receptor beta in the anteroventral periventricular nucleus of the rat preoptic area: Implication in luteinizing hormone surge PNAS, March 5, 2002; 99(5): 3306 - 3311. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Endocrinology | Endocrine Reviews | J. Clin. End. & Metab. |
| Molecular Endocrinology | Recent Prog. Horm. Res. | All Endocrine Journals |
