Indomethacin induces rat uterine contractions in vitro and alters reactivity to calcium and acetylcholine.
The initial contractions of uteri in vitro from castrated, estrogen-treated rats, were markedly diminished following replacement with fresh bathing medium. Indomethacin and aspirin (10(-5) to 10(-4)M) strongly stimulated such quiescent preparations and reduced their subsequent responsiveness to Ca++. Reintroducing the initial bathing medium (which contained prostaglandin-like material), or adding prostaglandin F2alpha to the fresh medium, initiated uterine contractions and restored responsiveness to calcium ion. Injections of indomethacin into castrated, estrogen-treated rats reduced initial in vitro uterine motility, abolished production of prostaglandin-like compounds, and prevented either indomethacin, aspirin, or Ca++ from stimulating uterine contractions. Uterine responsiveness to acetylcholine in vitro was significantly reduced in rats pretreated with indomethacin.
D000109:Acetylcholine / Q000494:pharmacology*; D000818:Animals; D002118:Calcium / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D005260:Female; D066298:In Vitro Techniques; D007213:Indomethacin / Q000494:pharmacology*; D011247:Pregnancy; D011453:Prostaglandins / Q000096:biosynthesis; D051381:Rats; D014590:Uterine Contraction / Q000187:drug effects*; D014599:Uterus / Q000378:metabolism
D011453:Prostaglandins; D000109:Acetylcholine; D002118:Calcium; D007213:Indomethacin