Reckelhoff J F, Zhang H, Granger J P
Department of Physiology and Biophysics, University of Mississippi Medical Center, Jackson 39216-4505, USA.
Hypertension. 1998 Jan;31(1 Pt 2):435-9. doi: 10.1161/01.hyp.31.1.435.
Studies were performed in intact male and female, gonadectomized male and female, and gonadectomized female rats given testosterone for 5 weeks to investigate the role played by testosterone in altered blood pressure control and pressure-natriuresis in male SHR. Serum testosterone levels reached a peak at 12 weeks of age in intact male SHR. Systolic blood pressure, measured weekly from 5 to 20 weeks of age, was similar between groups until 12 weeks of age when blood pressure became higher in males (195+/-3 mm Hg) than in females (168+/-3 mm Hg) or males castrated at 4 weeks (173+/-4 mm Hg). At 17 to 19 weeks direct measurement of arterial pressure in anesthetized rats confirmed that mean arterial pressure was higher in male (182+/-1 mm Hg) than in female (159+/-2 mm Hg) and castrated male SHR (159+/-2 mm Hg). In addition, testosterone (5 mg in Silastic pellets, SC for 5 weeks) administered to ovariectomized (ovx+T) females caused arterial pressure to increase by mm 11% (175+/-2 mm Hg), which was significantly higher than in intact female, castrated male, or untreated ovariectomized (ovx) female SHR (158+/-2 mm Hg). Acute pressure-natriuresis was blunted in male SHR compared with females, castrated males, or ovx females, in which this relationship was similar. Pressure-natriuresis was also blunted in ovx+T females as found in intact male SHR. These data support the hypothesis that male sex hormones contribute to the exacerbation of hypertension in SHR by reducing pressure-natriuresis.
对完整的雄性和雌性、去势的雄性和雌性以及接受睾酮处理5周的去势雌性大鼠进行了研究，以探讨睾酮在雄性自发性高血压大鼠（SHR）血压控制改变和压力-利钠作用中所起的作用。完整雄性SHR的血清睾酮水平在12周龄时达到峰值。从5至20周龄每周测量收缩压，在12周龄之前各实验组之间相似，12周龄时雄性（195±3 mmHg）血压高于雌性（168±3 mmHg）或4周龄时去势的雄性（173±4 mmHg）。在17至19周时，对麻醉大鼠直接测量动脉压证实，雄性（182±1 mmHg）平均动脉压高于雌性（159±2 mmHg）和去势雄性SHR（159±2 mmHg）。此外，对去卵巢（ovx+T）的雌性大鼠皮下植入含5 mg睾酮的硅橡胶丸5周，导致动脉压升高11%（175±2 mmHg），显著高于完整雌性、去势雄性或未处理的去卵巢（ovx）雌性SHR（158±2 mmHg）。与雌性、去势雄性或ovx雌性相比，雄性SHR的急性压力-利钠作用减弱，后三者的这种关系相似。ovx+T雌性大鼠的压力-利钠作用也如完整雄性SHR一样减弱。这些数据支持以下假说：雄性性激素通过降低压力-利钠作用导致SHR高血压加重。
