Relations between the effects of histamine, pheniramin and metiamide on spontaneous motility and the formation of cyclic AMP in the isolated rat uterus.
Histamine (5 X 10(-6) to 10(-3) M) depressed the spontaneous motility of the isolated rat uterus in a dose-dependent manner. Under these conditions uterine cyclic AMP was raised up to 92%. Both effects, uterine relaxation and cyclic AMP accumulation after 2 min could be inhibited dose dependently by the H2-antihistaminic compound metiamide (1.7 X 10(-6) M to 1.7 X 10(-4) M). By contrast, the H1-antagonist pheniramin (4.4 X 10(-5) M) was ineffective. It was concluded that the histamine-induced inhibition of rat uterine motility is mediated by cyclic AMP which is formed in response to stimulation of H2-histaminergic receptors.
D000818:Animals; D000242:Cyclic AMP / Q000096:biosynthesis*; D005260:Female; D006632:Histamine / Q000494:pharmacology*; D006634:Histamine H1 Antagonists / Q000494:pharmacology; D066298:In Vitro Techniques; D008785:Metiamide / Q000494:pharmacology*; D010632:Pheniramine / Q000494:pharmacology*; D051381:Rats; D011955:Receptors, Drug; D013890:Thiourea / Q000031:analogs & derivatives*; D014590:Uterine Contraction / Q000187:drug effects*; D014599:Uterus / Q000187:drug effects / Q000378:metabolism*
D006634:Histamine H1 Antagonists; D011955:Receptors, Drug; D010632:Pheniramine; D008785:Metiamide; D006632:Histamine; D000242:Cyclic AMP; D013890:Thiourea