孕期激素反应的反射调节。

Reflex regulation of hormonal responses during pregnancy.

Keller-Wood M

Department of Pharmacodynamics, College of Pharmacy, University of Florida, Gainesville 32610, USA.

Clin Exp Pharmacol Physiol. 1995 Feb;22(2):143-51. doi: 10.1111/j.1440-1681.1995.tb01971.x.

Abstract

During pregnancy in most species, the resting levels of plasma angiotensin II, plasma ACTH (corticotropin) are increased. The concentration of vasopressin is also increased relatively to the osmolality in rats and in humans. 2. In the pregnant state mean arterial pressure is decreased, despite an increase in blood volume. Vasopressin and ACTH responses to hypotension are altered in pregnant ewes; the relationship between mean arterial pressure and vasopressin or ACTH response is shifted to the left, consistent with a change in set-point for regulation of mean arterial pressure. The vasopressin and cortisol responses to hypotensive haemorrhage are also altered in the pregnant dog; in this case the slope of the relation between mean arterial pressure and hormone response is decreased. 3. The decrease in hormone responses to hypotension is stimulus-specific; ACTH responses to hypoglycaemia are increased in the pregnant ewe and AVP responses to hyperosmolality are not altered in the pregnant ewe. 4. The heart rate responses to hypotension are also decreased in pregnant ewes, consistent with the observation that baroreflex responses are decreased in the pregnant rat. 5. The data suggest that a change in regulation of arterial pressure alters the hormonal responses to hypotension in the pregnant state.

摘要

在大多数物种的孕期，血浆血管紧张素II、血浆促肾上腺皮质激素（促肾上腺皮质素）的静息水平会升高。在大鼠和人类中，抗利尿激素的浓度相对于渗透压也会升高。2. 在怀孕状态下，尽管血容量增加，但平均动脉压会降低。怀孕母羊对抗低血压时血管升压素和促肾上腺皮质激素的反应发生改变；平均动脉压与血管升压素或促肾上腺皮质激素反应之间的关系向左移动，这与平均动脉压调节设定点的变化一致。怀孕犬对抗低血压性出血时血管升压素和皮质醇的反应也发生改变；在这种情况下，平均动脉压与激素反应之间关系的斜率降低。3. 激素对抗低血压反应的降低具有刺激特异性；怀孕母羊对低血糖的促肾上腺皮质激素反应增加，而对高渗的抗利尿激素反应在怀孕母羊中未改变。4. 怀孕母羊对抗低血压时的心率反应也降低，这与怀孕大鼠压力反射反应降低的观察结果一致。5. 数据表明，动脉压调节的变化会改变怀孕状态下激素对抗低血压的反应。