McCalden T A
Br J Pharmacol. 1975 Feb;53(2):183-92. doi: 10.1111/j.1476-5381.1975.tb07348.x.
1 The in vitro action of oestradiol-17-beta (0.1, 1.0 and 10.0 mug/ml) and progesterone (0.1, 1.0 and 10.0 mug/ml) on the spontaneous activity of the portal veins in female rats at different stages of gestation was studied. 2 Progesterone caused the spontaneous mechanical activity in the rat portal vein to decrease in amplitude and increase in frequency. This action was dose-dependent and the sensitivity of the tissue decreased throughout pregnancy. 3 Oestradiol-17-beta had a biphasic effect on spontaneous mechanical activity in the rat portal vein. At 0.1 mug/ml the vessel was stimulated while a similar effect to progesterone occurred with higher concentrations. The tissue was more sensitive to oestradiol at 7 days of gestation than at either the 10-14 or 17-21 day periods of gestation. 4 These effects of oestradiol and progesterone were still seen after blockade of the beta-adrenoceptors. 5 Hydrocortisone (10 mug/ml) had no inhibitory effect on the spontaneous mechanical activity of the vein. 6 The veins from the 17-21 days pregnant animals showed a smaller amplitude of contraction than comparable non-pregnant females.
1 研究了雌二醇 - 17 - β（0.1、1.0和10.0微克/毫升）和孕酮（0.1、1.0和10.0微克/毫升）对处于不同妊娠阶段的雌性大鼠门静脉自发活动的体外作用。2 孕酮使大鼠门静脉的自发机械活动幅度减小、频率增加。此作用呈剂量依赖性，且整个孕期组织的敏感性降低。3 雌二醇 - 17 - β对大鼠门静脉的自发机械活动有双相作用。浓度为0.1微克/毫升时血管受到刺激，而较高浓度时则出现与孕酮类似的作用。妊娠7天时组织对雌二醇的敏感性高于妊娠10 - 14天或17 - 21天期间。4 β - 肾上腺素能受体阻断后，仍可见到雌二醇和孕酮的这些作用。5 氢化可的松（10微克/毫升）对静脉的自发机械活动无抑制作用。6 妊娠17 - 21天动物的静脉收缩幅度小于可比的未孕雌性动物。
