Chimura T
Nihon Sanka Fujinka Gakkai Zasshi. 1985 May;37(5):691-5.
Beta-adrenoceptor blockade (beta-blocker) has recently been introduced for use in treating hypertension of pregnancy. The aim of this investigation is to determine the effects of beta-blocker (alprenolol and labetalol) on parturition and on the fetal cardiovascular and metabolic system in normotensive pregnant rats. The continuous administration of alprenolol to pregnant Wistar rats revealed the following: a small placenta intrauterine growth retardation delayed parturition intrauterine death (21.8%) morbidity (30.3%) and, hypoglycemia of neonates. In the cases which received the administration of both labetalol and alprenolol, the growth of fetuses was retarded. However, there was twice as much growth retardation of the fetuses treated with alprenolol. No other abnormalities were observed. The administration of alprenolol in pregnant rat uteri (in vitro) resulted in stimulation of myometrial contractility (oxytocic reaction) and lowered the c-AMP levels in the bath medium. However, when labetalol was administered, uterine activity was reduced in a dose-dependent manner (tocolytic reaction) with a concurrent rise in c-AMP levels in the bath medium. The effect of alprenolol on rat uterine blood flow using the thermocouple method resulted in a decrease of 18-30 percent but with labetalol there was only a slight decrease (0-5%).
β-肾上腺素能受体阻滞剂（β受体阻滞剂）最近已被用于治疗妊娠高血压。本研究的目的是确定β受体阻滞剂（阿普洛尔和拉贝洛尔）对血压正常的妊娠大鼠分娩以及胎儿心血管和代谢系统的影响。对妊娠Wistar大鼠持续给予阿普洛尔后发现以下情况：胎盘较小、子宫内生长迟缓、分娩延迟、子宫内死亡（21.8%）、发病率（30.3%）以及新生儿低血糖。在同时接受拉贝洛尔和阿普洛尔给药的情况下，胎儿生长迟缓。然而，用阿普洛尔治疗的胎儿生长迟缓程度是前者的两倍。未观察到其他异常情况。在妊娠大鼠子宫内（体外）给予阿普洛尔会刺激子宫肌层收缩（催产反应）并降低浴液培养基中的环磷酸腺苷（c-AMP）水平。然而，给予拉贝洛尔时，子宫活动以剂量依赖方式降低（宫缩抑制反应），同时浴液培养基中的c-AMP水平升高。用热电偶法测定阿普洛尔对大鼠子宫血流量的影响导致血流量减少18% - 30%，但使用拉贝洛尔时血流量仅略有减少（0% - 5%）。
