短期给予雌激素可增强雄性大鼠肾血管对加压素的敏感性

INCREASED RENAL VASCULAR SENSITIVITY TO ARGININE VASOPRESSIN IN ESTROGEN-TREATED MALE RATS

研究短期给予雌激素（每日皮下注射１７－β－雌二醇１００μｇ／ｋｇ，共３ｄ）对雄性大鼠肾血管反应性的影响。应用多普勒超声技术测量大鼠肾动脉血流管（ＲＢＦ），并计算肾血管传导性（ＲＶＣ）。比较雌激素处理组和对照组ＲＢＦ、ＲＶＣ对加压素和去甲肾上腺素的剂量反应曲线及对巯甲丙脯酸的反应。数据用方差分析和ｔ检验。结果：处理组大鼠ＲＢＦ和ＲＶＣ对加压素的剂量反应曲线较对照组显著左移，对巯甲丙脯酸的反应也显著高于对照组，两组对去甲肾上腺素的剂量反应曲线几乎相同。结论：雌激素处理增强了大鼠肾血管对加压素的敏感性，还可能激活了肾素血管紧张素系统，由此推测雌激素处理大鼠肾血管对加压素的敏感性增加可能与肾素血管紧张素系统的激活有关。

PURPOSE Estrogen has been shown to be involved in the regulation of the biological actions of vasoactive agents. In this study, the effects of short-time administration of estradiol (100μg/kg body weight, sc injection every day for 3 days) on renal vascular sensitivity in male rats were investigated.METHODS By using Doppler ultrasound to measure the renal blood flow (RBF) and calculate the renal vascular conductance(RVC). The dose-response curves for arginine vasopressin (AVP) and norepinephrine, and the response to captopril in RBF and RVC were compared between the estradiol- treated and control rats. Data were analyzed with analysis of variance and paired t test.RESULTS Compared with the control group, the dose- response curves for AVP in RBF and RVC exhibited a significant leftward shift in male rats treated with 17-β-estradiol; the coresponding dose-response curves to norepinephrine were similar;the effects of captopril on RBF and RVC were significantly greater.CONCLUSIONS The administration of estradiol increases the renal vascular sensitivity to AVP and possibly potentiates the renin-angiotensin system(RAS), and the potentiation of AVP by estradiol may be related to the activation of the RAS.