Stone J D, Crofton J T, Share L
Department of Physiology and Biophysics, University of Tennessee, Memphis 38163.
Am J Physiol. 1992 Nov;263(5 Pt 2):R1030-4. doi: 10.1152/ajpregu.1992.263.5.R1030.
In conscious, unrestrained rats, the intracerebroventricular injection of the cholinergic agonist, carbachol, or angiotensin II resulted in the transient stimulation of vasopressin secretion, elevation of mean arterial blood pressure, and reduction of heart rate. After the injection of carbachol (25 ng) into a lateral cerebral ventricle, the plasma vasopressin concentration in male rats was increased to twice that of female rats in each phase of the estrous cycle; mean arterial blood pressure was elevated more in males than females, whereas heart rate fell to the same extent in both sexes. In contrast, the increase in the plasma vasopressin concentration of males after the injection of angiotensin II (20 ng) was one-half that of females, and the hypertensive and bradycardic responses were similar in both sexes. Phase of the female estrous cycle had no effect on the responses to either agent. These findings indicate that central cholinergic and angiotensinergic mechanisms controlling vasopressin release are influenced differently by gender. The role of the gonadal steroid hormones in these mechanisms remains to be determined.
在清醒、未受束缚的大鼠中，脑室内注射胆碱能激动剂卡巴胆碱或血管紧张素II会导致血管加压素分泌短暂增加、平均动脉血压升高以及心率降低。向大鼠侧脑室注射卡巴胆碱（25纳克）后，雄性大鼠血浆血管加压素浓度在发情周期各阶段均升高至雌性大鼠的两倍；雄性大鼠平均动脉血压升高幅度大于雌性，而两性心率下降幅度相同。相比之下，注射血管紧张素II（20纳克）后雄性大鼠血浆血管加压素浓度的升高幅度仅为雌性大鼠的一半，且两性的高血压和心动过缓反应相似。雌性发情周期阶段对两种药物的反应均无影响。这些发现表明，控制血管加压素释放的中枢胆碱能和血管紧张素能机制受性别的影响不同。性腺类固醇激素在这些机制中的作用仍有待确定。
