Nuwayhid B, Brinkman C R, Woods J R, Martinek H, Assali N S
Am J Obstet Gynecol. 1975 Nov 1;123(5):495-504. doi: 10.1016/0002-9378(75)90037-x.
Effects of estrogen administration on systemic and regional circulation were studied in normotensive and renal hypertensive, chronically instrumented nonpregnant and pregnant ewes. Arterial pressure, cardiac output, and uterine, renal, superior mesenteric, and iliac blood flows, as well as uterine oxygen transfer, were monitored before and after intravenous administration of Premarin or estradiol-17 beta. The results show that: (1) estrogen administration produces a marked decrease in uterine vascular resistance and increase in uterine blood flow and oxygen transfer, lasting for about 2 hours; (2) arterial pressure, cardiac output, and other regional blood flows were not affected by estrogens; (3) the magnitude of uterine vasodilatation produced by estrogens was greater in the hypertensive than in the normotensive animals; it was also greater in the nonpregnant than in the pregnant state; these findings indicate that the magnitude of uterine vasodilatation depends on the status of the uterine vascular resistance in the resting state; (4) blockade of the autonomic nervous system at various levels, as well as administration of a mild antihistaminic agent, failed to alter the magnitude of the estrogen-induced uterine vasodilatation. These results indicate that estrogens act directly on the uterine vascular bed and produce a redistribution of flows and resistances in the body; the precise sites of this redistribution are not as yet determined.
在正常血压和肾性高血压、长期植入监测仪器的未孕和怀孕母羊中，研究了雌激素给药对全身和局部循环的影响。在静脉注射倍美力或17β-雌二醇前后，监测动脉血压、心输出量、子宫、肾脏、肠系膜上动脉和髂动脉血流量以及子宫氧转运。结果表明：（1）雌激素给药可使子宫血管阻力显著降低，子宫血流量和氧转运增加，持续约2小时；（2）动脉血压、心输出量和其他局部血流量不受雌激素影响；（3）雌激素引起的子宫血管舒张程度在高血压动物中比正常血压动物更大；在未孕状态下比怀孕状态下也更大；这些发现表明子宫血管舒张程度取决于静息状态下子宫血管阻力的状态；（4）在不同水平阻断自主神经系统以及给予轻度抗组胺药，均未能改变雌激素诱导的子宫血管舒张程度。这些结果表明，雌激素直接作用于子宫血管床，并在体内产生血流和阻力的重新分布；这种重新分布的确切部位尚未确定。
