[Effects of highly concentrated estrogen and progesterone on the contractile mechanism of the uterine smooth muscles].
The effects of a high concentrated estrogen and progesterone were studied on the contractile activities in isolated myometrial strips from humans and rats by recording isometric tension development. The contractions were reduced by 10(-5)-3 X 10(-5) M estrone (E1), estradiol (E2), estriol (E3), and progesterone (P) in non pregnant human uterus. The contractions were reduced by 10(-6)-10(-4) M E1, E2, E3 and P in non pregnant rat uterus. The contractions induced by 10(-8)-10(-5) M PGE2 and PGF2 alpha were reduced by 10(-5) M E2 and P in non pregnant rat uterus. The contractions induced by 10(-10)-3 X 10(-8) M oxytocin were reduced by 10(-5) M E2 and P in non pregnant rat uterus. The contractures induced by 10(-4)-10(-2) M Ca2+ were reduced by 10(-5) M E2 and P in non pregnant rat uterus. The effects of a high concentrated estrogen and progesterone were studied on Ca2+ influx and Ca2+ release from intracellular Ca store in the depolarized uterine smooth muscle cells from non pregnant rats. The inhibitory effects on the contractility by 3 X 10(-6)-3 X 10(-5) M E2, E3 and P supported the suggestion that estrogen and progesterone have an inhibitory action on Ca2+ influx and Ca2+ release from intracellular Ca store.
D000818:Animals; D002118:Calcium / Q000378:metabolism / Q000494:pharmacology; D004347:Drug Interactions; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006801:Humans; D066298:In Vitro Techniques; D009215:Myometrium / Q000378:metabolism; D010121:Oxytocin / Q000494:pharmacology; D011374:Progesterone / Q000494:pharmacology*; D011453:Prostaglandins / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D014590:Uterine Contraction / Q000187:drug effects*
D004967:Estrogens; D011453:Prostaglandins; D011374:Progesterone; D010121:Oxytocin; D002118:Calcium