Interaction between nitric oxide and prostaglandin e2 pathways in
pregnant rat uteri.
Dong, Yuan-Lin, and Chandrasekhar Yallampalli.
Department of Obstetrics & Gynecology, The University of Texas
Medical Branch, Galveston, Texas 77555
APStracts 2:0244E, 1995.
We examined the possible interrelationship between NO and
cyclooxygenase (COX) products in the uterus during pregnancy and
labor. Results indicate that: (1) rat uteri during labor, at term,
demonstrated a 69% decrease in nitrite production and 217% increase
in PGE2 production compared with that during day 18 of pregnancy; (2)
interleukin-1[beta] (IL-1[beta]) induced a pronounced elevation of
both nitrites and PGE2 in rat uteri; (3) DETA/NO, a donor of NO,
induced a significant increase of PGE2 production by the uterus in a
dose-dependent manner; (4) L-NAME, an inhibitor of NO synthesis,
markedly inhibited IL-1[beta]-induced nitrite and PGE2 production in
rat uteri. This inhibitory action was reversed by coincubation with
L-arginine; (5) exogenous PGE2 significantly inhibited IL-1[beta]
-induced nitrite production, but not constitutive nitrite production;
and (6) inhibition of endogenous PGE2 by indomethacin substantially
increased IL-1[beta]-induced nitrite production. Thus, the
interaction between NO and COX pathways might be important in the
regulation of uterine contractility during pregnancy and labor.
Received 10 July 1995; accepted in final form 12 October 1995..
APS Manuscript Number E317-5.
Article publication pending Am. J. Physiol. (Endocrinol. Metab.).
ISSN 1080-4757 Copyright 1995 The American Physiological Society.
Published in APStracts on 8 December 95