Lieb S M, Cabalum T, Zugaib M, Erkkola R, Tabsh K, Ushioda E, Nuwayhid B S, Brinkman C R, Assali N S
Am J Physiol. 1980 Feb;238(2):H209-13. doi: 10.1152/ajpheart.1980.238.2.H209.
The circulatory responses to progressively increasing doses of angiotensin II were studied in the same group of chronically instrumented unanesthetized pregnant sheep during three consecutive periods: a) normotensive with intact kidneys; b) normotensive with unilateral nephrectomy; and c) one-kidney hypertension. The results show that 1) the pressor response to a given dose of angiotensin was significantly greater in the normotensive than in the hypertensive condition; 2) uterine blood flow decreased markedly with the development of hypertension; 3) uterine circulatory response to angiotensin depended on the dosage; the response was less the the hypertensive than in the normotensive condition; 4) renal blood flow decreased and renal vascular resistance increased during angiotensin infusion, but the response was less in the hypertensive than in the normotensive condition; the response of the renal circulation decreased with increasing doses of angiotensin. These observations suggest a generalized vascular refractoriness to exogenous angiotensin II in the pregnant ewe with experimental renal hypertension.
在同一组长期植入仪器的未麻醉怀孕绵羊中，连续三个阶段研究了对逐渐增加剂量的血管紧张素II的循环反应：a）肾脏完整的正常血压状态；b）单侧肾切除后的正常血压状态；c）单肾高血压状态。结果表明：1）在正常血压状态下，对给定剂量血管紧张素的升压反应明显大于高血压状态；2）随着高血压的发展，子宫血流量显著减少；3）子宫对血管紧张素的循环反应取决于剂量；高血压状态下的反应小于正常血压状态；4）在输注血管紧张素期间，肾血流量减少，肾血管阻力增加，但高血压状态下的反应小于正常血压状态；肾循环的反应随着血管紧张素剂量的增加而降低。这些观察结果表明，患有实验性肾性高血压的怀孕母羊对外源性血管紧张素II存在普遍的血管不应性。
