Chimura T, Inoue K
Nihon Sanka Fujinka Gakkai Zasshi. 1981 Aug;33(8):1167-72.
beta 2-Stimulant are at present the most effective tocolytic agents. The purpose of this paper is to outline the beta 1-, beta 2-effects of ritodrine in animal experiments. 1) In the pregnant rat uterus at term, ritodrine and terbutaline showed the potent effect. The c-GMP level in the bath medium was significantly decreased by the administration of ritodrine, while the c-AMP levels was significantly increased. 2) When the changes in the maternal serum c-AMP and c-GMP levels after the administration of ritodrine were examined, these results coincided with those obtained experiments in vitro. But decreased in c-AMP and c-GMP levels by administering beta-blocker. The c-AMP and c-GMP levels of placenta, liver, uterus and fetus showed similar patterns, especially c-AMP in the uterine and fetal tissues increased when ritodrine was administered. 3) The administration of ritodrine and terbutaline at the last trimester of pregnancy led to the increased, showing dose-response relationship, in the heart rate of mother and fetus in rabbits. 4) The effect of ritodrine on fetal and neonatal serum glucose concentrations was examined in rats. Sustained hypoglycemia was observed in fetus and neonate delivered within 18 hours of the termination of administration (ritodrine, 10-20 mg, sc).
β2激动剂是目前最有效的宫缩抑制剂。本文旨在概述利托君在动物实验中的β1、β2效应。1）在足月妊娠大鼠子宫中，利托君和特布他林显示出强效作用。给予利托君后，浴槽培养基中的环鸟苷酸（c-GMP）水平显著降低，而环磷酸腺苷（c-AMP）水平显著升高。2）当检测给予利托君后母体血清c-AMP和c-GMP水平的变化时，这些结果与体外实验所得结果一致。但给予β受体阻滞剂后c-AMP和c-GMP水平降低。胎盘、肝脏、子宫和胎儿的c-AMP和c-GMP水平呈现相似模式，尤其是给予利托君后，子宫和胎儿组织中的c-AMP增加。3）在妊娠晚期给予利托君和特布他林导致兔母体和胎儿心率增加，呈剂量反应关系。4）在大鼠中检测了利托君对胎儿和新生儿血清葡萄糖浓度的影响。在给药结束后18小时内分娩的胎儿和新生儿中观察到持续性低血糖（利托君，10 - 20毫克，皮下注射）。
