雄激素对高盐饮食状态下雄性大鼠血管内皮功能的影响

The effect of androgen in vascular endothelial function of male rats under high-salt diet

摘要:

目的 探讨不同水平雄激素对高盐饮食状态下雄性大鼠血管内皮功能的影响。方法 雄性Wistar大鼠32只随机分为4组，每组各8只：假手术组（Sham），去势组（Cas），去势后补充睾酮组（TC），去势后补充睾酮和氟他胺组（FTC）。各组均以8%NaCl高盐颗粒饲料喂养，Sham组施以假手术，Cas、TC及FTC组均施以去势手术。TC及FTC组予以丙酸睾酮（TP）2mg/（kg?2d）皮下注射，FTC组同时予以氟他胺1mg/（kg?d）灌胃，持续8周。尾动脉脉压法测定各组实验前、实验4周、实验8周后尾动脉血压，8周后酶联免疫吸附测定法（ELISA）测定血清中睾酮（T）、内皮素1（ET-1）的浓度，比色法测定血浆中一氧化氮（NO）水平。结果 （1）与Sham组血压相比，Cas组和FTC组明显下降[Cas组：（124.8±4.4）vs（135.9±3.7）mmHg，P＜0.01；FTC组：（127.7±3.0）vs（135.9±3.7）mmHg，P＜0.01]；与基础血压相比，Sham组和TC组明显升高（P＜0.01）；（2）与Sham组T浓度相比，Cas组的明显下降[（0.26±0.02）vs（3.15±0.54）μg/L，P＜0.01]，而FTC组明显升高[（5.47±1.29）vs（3.15±0.54）μg/L，P＜0.01]；（3）与Sham组血清ET-1浓度相比，Cas组和FTC组明显下降[Cas组：（0.77±0.23）vs（1.08±0.15）μg/L，P＜0.01；FTC组：（0.80±0.21）vs（1.08±0.15）μg/L，P＜0.05]；TC组差异无统计学意义（P＞0.05）；（4）与Sham组NO浓度相比，Cas组和FTC组明显升高[Cas组：（42.37±15.74）vs（17.20±7.32）mmol/L，P＜0.01；FTC组：（33.44±8.50）vs（17.20±7.32）mmol/L，P＜0.01]；TC组差异无统计学意义（P＞0.05）。结论 高盐饮食下，雄激素水平的变化可能影响雄性大鼠血管内皮功能。

Abstract:

Objective To explore the effect of different levels of androgen in the vascular endothelial function of high-salt fed male rats. Methods Thirty-two Wistar rats were randomly assigned to 4 groups, sham-operation (Sham) group, castration (Cas) group, testosterone supplement after castration (TC) group, and flutamide-treated testosterone supplemented castrated (FTC) group, with eight rats in each. All animals were fed high-salt diet (8% NaCl) for 8 weeks. Animals in Sham group received sham operation, while those in Cas, TC and FTC group received surgical castration. Subcutaneous injection of testosterone propionate (TP) 2mg/(kg?2d) was performed in TC and FTC groups, and intragastric administration of flutamide 1mg/(kg? d) in FTC group continuously for 8 weeks. The blood of tail artery was measured at baseline, 4 and 8 weeks after experiment respectively. At 8 weeks after experiment, content of testosterone (T) and endothelin-1(ET-1) in serum were determined by enzyme-linked immunosorbent assay (ELISA), and colorimetric assay was used to detect the level of nitric oxide(NO) in plasma. Results (1) Compared with Sham group, blood pressure at 4 and 8 weeks declined significantly in Cas group and FTC group [Cas: (124.8±4.4) vs (135.9±3.7)mmHg, P＜0.01; FTC:(127.7±3.0) vs (135.9±3.7)mmHg, P＜0.01], while increased significantly (P＜0.01) from baseline in Sham and TC groups. (2) Compared with Sham group, serum T content obviously decreased in Cas group [(0.26±0.02) vs (3.15±0.54)μg/L, P＜0.01], and increased significantly in FTC groups [(5.47±1.29) vs (3.15±0.54)μg/L, P＜0.01]. (3) Compared with Sham group, serum ET-1 content declined significantly in Cas group and FTC group [Cas: (0.77±0.23) vs (1.08±0.15)μg/L, P＜0.01; FTC: (0.80±0.21) vs (1.08±0.15)μg/L, P＜0.05], and had no significant difference with TC group (P＞0.05). (4) NO content, compared with Sham group, increased significantly in Cas group and FTC group [Cas: (42.37±15.74) vs (17.20±7.32)mmol/L, P＜0.01; FTC: (33.44±8.50) vs (17.20±7.32)mmol/L, P＜0.01], and had no significant difference with TC group (P＞0.05). Conclusion Under high-salt diet, change of androgen can influence vascular endothelial function of male rats.