Deactivation of the uterus during normal and premature labor by the calcium antagonist nicardipine.

摘要: Abstract Nicardipine, a calcium antagonist, suspended the spontaneous activity of excised rabbit uterus at concentration 1 μg/ml and abolished electrical excitability 10 μg/ml. In situ, single doses 100 500 μg reversibly postpartum rat (n = 22) for 34 ± 6 minutes 94 9 minutes, respectively. Furthermore, intrauterine administration prostaglandin F 2α or oxytocin failed to elevate pressure in rats 18) injected with an average dose 207 28 nicardipine. The nicardipine 19) immediately after delivery first fetus arrested labor, subsequent fetuses was markedly delayed as compared control 20). Similarly, when premature labor induced by ovariectomy (OVX) on day 16, OVX 6) receiving 5 μg/day estradiol delivered 82% within 48 hours OVX, whereas treated 7) only 4% fetuses. All were alive normal. Since estradiol, progesterone, profiles heart plasma, uterine vein tissue experimental similar, prevention resulted from antagonistic action calcium.