| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
Endocrinology, Vol 133, 1511-1519, Copyright © 1993 by Endocrine Society
ARTICLES |
A Hinko and MS Soloff
Department of Surgery, Medical College of Ohio, Toledo 43699-1008.
Oxytocin (OT) receptors (OTR) in rabbit amnion increase more than 200- fold at the end of gestation. In the present report, we studied the basis of this up-regulation. Incubation of amnion cells with cortisol (20 nM) for 24 h increased the amount of 125I-labeled OT antagonist bound by 16- to 18-fold. The effects of cortisol were dose and steroid dependent. Administration of glucocorticoid to pregnant does also increased the concentration of OTRs in amnion. The effects of cortisol in vitro were potentiated by the addition of forskolin (50 microM), so that OTR number increased by as much as 182 times. The effects of cortisol and forskolin, either separately or in combination, were inhibited by activation of protein kinase-C or coincubation with transforming growth factor-alpha (10 nM). Cyclosporin-A (5 microM) selectively inhibited cortisol-induced rises in the OTR concentration. The addition of cortisol to amnion cells increased OT-stimulated prostaglandin E2 (PGE2) release almost 100-fold; the combination of forskolin and cortisol increased the PGE2 response to OT about 5600 times. Judging from the greater effects on PGE2 release, these results suggest that forskolin and cortisol up-regulate the signal response mechanism to OT as well as the OTR concentration. The findings show that changes occurring in the amnion in vivo can be mimicked in vitro, and they elucidate the mechanism of up-regulation of OTR concentrations.
This article has been cited by other articles:
 |
|
 |
|
  Y.-J. Jeng, S. L. Soloff, G. D. Anderson, and M. S. Soloff Regulation of Oxytocin Receptor Expression in Cultured Human Myometrial Cells by Fetal Bovine Serum and Lysophospholipids Endocrinology, January 1, 2003; 144(1): 61 - 68. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 G. Gimpl and F. Fahrenholz The Oxytocin Receptor System: Structure, Function, and Regulation Physiol Rev, April 1, 2001; 81(2): 629 - 683. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y.-J. Jeng, D. Liebenthal, Z. Strakova, K. L. Ives, M. R. Hellmich, and M. S. Soloff Complementary Mechanisms of Enhanced Oxytocin-Stimulated Prostaglandin E2 Synthesis in Rabbit Amnion at the End of Gestation Endocrinology, November 1, 2000; 141(11): 4136 - 4145. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 S. Hoare, J. A. Copland, Z. Strakova, K. Ives, Y.-J. Jeng, M. R. Hellmich, and M. S. Soloff The Proximal Portion of the COOH Terminus of the Oxytocin Receptor Is Required for Coupling to Gq, but Not Gi. INDEPENDENT MECHANISMS FOR ELEVATING INTRACELLULAR CALCIUM CONCENTRATIONS FROM INTRACELLULAR STORES J. Biol. Chem., October 1, 1999; 274(40): 28682 - 28689. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
Y.-J. Jeng, S. J. Lolait, and M. S. Soloff Induction of Oxytocin Receptor Gene Expression in Rabbit Amnion Cells Endocrinology, August 1, 1998; 139(8): 3449 - 3455. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. A. Duina, H.-C. J. Chang, J. A. Marsh, S. Lindquist, and R. F. Gaber A Cyclophilin Function in Hsp90-Dependent Signal Transduction Science, December 6, 1996; 274(5293): 1713 - 1715. [Abstract] [Full Text]
|
|
|
|
 |
|
 J. B. Derks, D. A. Giussani, L. M. Van Dam, S. L. Jenkins, J. A. Winter, X. F. Zhao, G. L. Hammond, and P. W. Nathanielsz Differential Effects of Betamethasone and Dexamethasone Fetal Administration of Parturition in Sheep Reproductive Sciences, November 1, 1996; 3(6): 336 - 341. [Abstract] [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 |
