title: Interaction between nitric oxide and prostaglandin E2 pathways in pregnant rat uteri.
abstract: We examined the possible interrelationship between nitric oxide (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 a 217% increase in prostaglandin E2 (PGE2) production compared with day 18 of pregnancy; 2) interleukin-1 beta (IL-1 beta) induced a pronounced elevation of both nitrites and PGE2 in rat uteri; 3) diethylenetriamine/NO, a donor of NO, induced a significant increase of PGE2 production by the uterus in a dose-dependent manner; 4) NG-nitro-L-arginine methyl ester, an inhibitor of NO synthesis, markedly inhibited IL-1 beta-induced nitrite and PGE2 in rat uteri; this inhibitory action was reversed by coincubation with L-arginine; 5)exogenous PGE2 significantly inhibited IL-1 beta-induced, 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.
authors.affiliation: Department of Obstetrics and Gynecology, The University of Texas Medical Branch, Galveston 77555, USA.
authors.forename: Y L
authors.initials: YL
authors.lastname: Dong
authors.forename: C
authors.initials: C
authors.lastname: Yallampalli
mesh_terms: D000818:Animals; D001120:Arginine / Q000031:analogs & derivatives* / Q000494:pharmacology; D015232:Dinoprostone / Q000502:physiology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D005260:Female; D007213:Indomethacin / Q000494:pharmacology; D007375:Interleukin-1 / Q000494:pharmacology*; D007743:Labor, Obstetric; D019331:NG-Nitroarginine Methyl Ester; D009569:Nitric Oxide / Q000502:physiology*; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors; D009573:Nitrites / Q000378:metabolism; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000378:metabolism*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D014599:Uterus / Q000187:drug effects / Q000378:metabolism*
chemical_list: D004791:Enzyme Inhibitors; D007375:Interleukin-1; D009573:Nitrites; D009569:Nitric Oxide; D001120:Arginine; D019001:Nitric Oxide Synthase; D011451:Prostaglandin-Endoperoxide Synthases; D015232:Dinoprostone; D019331:NG-Nitroarginine Methyl Ester; D007213:Indomethacin