| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Articles |
First Department of Internal Medicine, Nagoya University School of Medicine, Nagoya 466, Japan
Address all correspondence and requests for reprints to: Yasumasa Iwasaki, M.D. First Department of Internal Medicine, Nagoya University School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466, Japan.
Although the effects of the various secretagogues on corticotropin
(ACTH) secretion have been well studied, their effects on the POMC gene
expression have not been thoroughly characterized. In this study, we
established a new model system using the AtT20 mouse corticotroph tumor
cell line transfected stably with a plasmid containing 0.7 kb of the
rat POMC 5' promoter-luciferase fusion gene. The responsiveness to
exogenous CRH improved markedly when the cells were cultured with low
serum medium (1% FBS) compared with serum rich medium (10%). Using
this culture condition, we examined the effects of not only CRH but
also other secretagogues such as catecholamines, vasopressin, and
angiotensin II, upon the transcriptional activity of the POMC gene. CRH
stimulated POMC promoter activity (3.5-fold increase) as well as cAMP
generation and ACTH secretion in a dose- and time-dependent manner,
with the maximal effect being observed 3–5 h after the start of
incubation. Catecholamines, especially epinephrine (10 nM
and above), also stimulated all parameters, although less potently than
CRH, and the effect was mimicked by the ß-, but not 
-adrenergic,
agonist, suggesting the involvement of the ß-adrenergic receptor. The
combined effects of epinephrine and CRH were greater in all parameters
than those of CRH alone, and the effects of both hormones were
completely blocked by H89, an inhibitor of protein kinase A.
Vasopressin and angiotensin II showed minimal effects on POMC
expression. Our results suggest that 1) catecholamines, as well as CRH,
positively regulate the POMC gene at physiological concentrations; 2)
the cAMP-PKA system is the common intracellular signaling pathway
for CRH and catecholamines; and 3) vasopressin and angiotensin II also
have weak but significant stimulatory effects on POMC promoter
activity.
This article has been cited by other articles:
 |
|
 |
|
  M. Perello, R. Stuart, and E. A. Nillni Prothyrotropin-releasing Hormone Targets Its Processing Products to Different Vesicles of the Secretory Pathway J. Biol. Chem., July 18, 2008; 283(29): 19936 - 19947. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Iwasaki, M. Nishiyama, T. Taguchi, M. Kambayashi, M. Asai, M. Yoshida, T. Nigawara, and K. Hashimoto Activation of AMP-activated protein kinase stimulates proopiomelanocortin gene transcription in AtT20 corticotroph cells Am J Physiol Endocrinol Metab, June 1, 2007; 292(6): E1899 - E1905. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 I. Murakami, S. Takeuchi, T. Kudo, S. Sutou, and S. Takahashi Corticotropin-releasing hormone or dexamethasone regulates rat proopiomelanocortin transcription through Tpit/Pitx-responsive element in its promoter J. Endocrinol., May 1, 2007; 193(2): 279 - 290. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 J. Cao, C. L. Cetrulo, and T. C. Theoharides Corticotropin-Releasing Hormone Induces Vascular Endothelial Growth Factor Release from Human Mast Cells via the cAMP/Protein Kinase A/p38 Mitogen-Activated Protein Kinase Pathway Mol. Pharmacol., March 1, 2006; 69(3): 998 - 1006. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 T. Nigawara, Y. Iwasaki, M. Asai, M. Yoshida, M. Kambayashi, H. Sashinami, K. Hashimoto, and T. Suda Inhibition of 11{beta}-Hydroxysteroid Dehydrogenase Eliminates Impaired Glucocorticoid Suppression and Induces Apoptosis in Corticotroph Tumor Cells Endocrinology, February 1, 2006; 147(2): 769 - 772. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. M. Soares, M. Thompson, and E. N. Chini Role of the Second-Messenger Cyclic-Adenosine 5'-Diphosphate-Ribose on Adrenocorticotropin Secretion from Pituitary Cells Endocrinology, May 1, 2005; 146(5): 2186 - 2192. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
S. Ma, M. J. Shipston, D. Morilak, and J. A. Russell Reduced Hypothalamic Vasopressin Secretion Underlies Attenuated Adrenocorticotropin Stress Responses in Pregnant Rats Endocrinology, March 1, 2005; 146(3): 1626 - 1637. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 E Yamamori, M Asai, M Yoshida, K Takano, K Itoi, Y Oiso, and Y Iwasaki Calcium/calmodulin kinase IV pathway is involved in the transcriptional regulation of the corticotropin-releasing hormone gene promoter in neuronal cells J. Mol. Endocrinol., December 1, 2004; 33(3): 639 - 649. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 Y. Iwasaki, M. Asai, M. Yoshida, T. Nigawara, M. Kambayashi, and N. Nakashima Dehydroepiandrosterone-Sulfate Inhibits Nuclear Factor-{kappa}B-Dependent Transcription in Hepatocytes, Possibly through Antioxidant Effect J. Clin. Endocrinol. Metab., July 1, 2004; 89(7): 3449 - 3454. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
K. Asaba, Y. Iwasaki, M. Yoshida, M. Asai, Y. Oiso, T. Murohara, and K. Hashimoto Attenuation by Reactive Oxygen Species of Glucocorticoid Suppression on Proopiomelanocortin Gene Expression in Pituitary Corticotroph Cells Endocrinology, January 1, 2004; 145(1): 39 - 42. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. Yamamori, Y. Iwasaki, Y. Oki, M. Yoshida, M. Asai, M. Kambayashii, Y. Oiso, and N. Nakashima Possible Involvement of Ryanodine Receptor-Mediated Intracellular Calcium Release in the Effect of Corticotropin-Releasing Factor on Adrenocorticotropin Secretion Endocrinology, January 1, 2004; 145(1): 36 - 38. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 C. Bousquet, V. Chesnokova, A. Kariagina, A. Ferrand, and S. Melmed cAMP Neuropeptide Agonists Induce Pituitary Suppressor of Cytokine Signaling-3: Novel Negative Feedback Mechanism for Corticotroph Cytokine Action Mol. Endocrinol., November 1, 2001; 15(11): 1880 - 1890. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
A. Nomura, Y. Iwasaki, M. Saito, Y. Aoki, E. Yamamori, N. Ozaki, K. Tachikawa, N. Mutsuga, M. Morishita, M. Yoshida, et al. Involvement of upstream open reading frames in regulation of rat V1b vasopressin receptor expression Am J Physiol Endocrinol Metab, May 1, 2001; 280(5): E780 - E787. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Morishita, Y. Iwasaki, E. Yamamori, A. Nomura, N. Mutsuga, M. Yoshida, M. Asai, Y. Oiso, and H. Saito Antidiabetic Sulfonylurea Enhances Secretagogue-Induced Adrenocorticotropin Secretion and Proopiomelanocortin Gene Expression in Vitro Endocrinology, September 1, 2000; 141(9): 3313 - 3318. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Slominski, J. Wortsman, T. Luger, R. Paus, and S. Solomon Corticotropin Releasing Hormone and Proopiomelanocortin Involvement in the Cutaneous Response to Stress Physiol Rev, July 1, 2000; 80(3): 979 - 1020. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
C. J. Rossant, R. D. Pinnock, J. Hughes, M. D. Hall, and S. McNulty Corticotropin-Releasing Factor Type 1 and Type 2{alpha} Receptors Regulate Phosphorylation of Calcium/Cyclic Adenosine 3',5'-Monophosphate Response Element-Binding Protein and Activation of p42/p44 Mitogen-Activated Protein Kinase Endocrinology, April 1, 1999; 140(4): 1525 - 1536. [Abstract] [Full Text]
|
|
|
|
|
|
A. Niiori-Onishi, Y. Iwasaki, N. Mutsuga, Y. Oiso, K. Inoue, and H. Saito Molecular Mechanisms of the Negative Effect of Insulin-Like Growth Factor-I on Growth Hormone Gene Expression in MtT/S Somatotroph Cells Endocrinology, January 1, 1999; 140(1): 344 - 349. [Abstract] [Full Text]
|
|
|
|
|
|
C. J. Auernhammer, V. Chesnokova, and S. Melmed Leukemia Inhibitory Factor Modulates Interleukin-1{beta}-Induced Activation of the Hypothalamo-Pituitary-Adrenal Axis Endocrinology, May 1, 1998; 139(5): 2201 - 2208. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
M. Katahira, Y. Iwasaki, Y. Aoki, Y. Oiso, and H. Saito Cytokine Regulation of the Rat Proopiomelanocortin Gene Expression in AtT-20 Cells Endocrinology, May 1, 1998; 139(5): 2414 - 2422. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y. Aoki, Y. Iwasaki, M. Katahira, Y. Oiso, and H. Saito Regulation of the Rat Proopiomelanocortin Gene Expression in AtT-20 cells. II: Effects of the Pituitary Adenylate Cyclase-Activating Polypeptide and Vasoactive Intestinal Polypeptide Endocrinology, May 1, 1997; 138(5): 1930 - 1934. [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 |
