|
|
||||||||
1 Departments of Pediatrics, Molecular Biology and Pharmacology, and Obstetrics and Gynecology, Washington University School of Medicine and St. Louis Children's Hospital, St. Louis, Missouri 63110; and 2 Division of Endocrinology, The Children's Hospital, Boston, Massachusetts 02115
Recent analysis of mice deficient in both oxytocin (OT) and cyclooxygenase-1 has shown that OT exerts significant effects on both the ovarian corpus luteum and the uterine myometrium during pregnancy. To better define the roles of OT during pregnancy, we evaluated OT action and OT receptor regulation in wild-type and OT-deficient knockout (KO) mice. Continuous infusion of OT revealed that OT can either delay labor at low doses or initiate preterm labor at high doses. The infusion rates of OT necessary for these effects were reduced in OT KO mice. The dose of OT that delayed labor also delayed the normal decrease in plasma progesterone late in gestation, implicating a primary effect on the corpus luteum. Consistent with this hypothesis, luteal OT receptor expression exceeded that of the myometrium until luteolysis occurred. We propose that the downregulation of OT receptors in the corpus luteum and induction of OT receptors in the myometrium serve to shift the predominant consequence of OT action during murine pregnancy from labor inhibition to labor promotion.
corpus luteum; knockout mice; labor; luteolysis; oxytocin receptor
This article has been cited by other articles:
![]() |
H. Endoh, T. Fujioka, H. Endo, Y. Inazuka, S. Furukawa, and S. Nakamura Stimulation of Fetal Hypothalamus Induces Uterine Contractions in Pregnant Rats at Term Biol Reprod, October 1, 2008; 79(4): 633 - 637. [Abstract] [Full Text] [PDF] |
||||
![]() |
Y. Li, H.-D. Je, S. Malek, and K. G. Morgan ERK1/2-mediated phosphorylation of myometrial caldesmon during pregnancy and labor Am J Physiol Regulatory Integrative Comp Physiol, January 1, 2003; 284(1): R192 - R199. [Abstract] [Full Text] [PDF] |
||||
![]() |
J. P. Granger Maternal and fetal adaptations during pregnancy: lessons in regulatory and integrative physiology Am J Physiol Regulatory Integrative Comp Physiol, December 1, 2002; 283(6): R1289 - R1292. [Full Text] [PDF] |
||||
![]() |
J. A. Copland, M. G. Zlatnik, K. L. Ives, and M. S. Soloff Oxytocin Receptor Regulation and Action in a Human Granulosa-Lutein Cell Line Biol Reprod, May 1, 2002; 66(5): 1230 - 1236. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |