睾酮对大鼠血管平滑肌细胞增殖的影响及其与雄激素受体水平变化的关系

Effect of testosterone on the proliferation of vascular smooth muscle cells and its relation with androgen receptor expression

目的 探讨睾酮及其拮抗剂对雄性大鼠血管平滑肌细胞增殖的影响及其与雄激素受体水平变化的关系。方法 采用贴块法培养雄性Sprague Dawley大鼠胸主动脉血管平滑肌细胞 ,分别用3 [H]胸腺嘧啶脱氧核苷掺入法和MTT还原法观察不同浓度睾酮及其拮抗剂氟他胺对血管平滑肌细胞增殖的影响 ,用免疫印迹分析 (Westernblot)法检测细胞中雄激素受体水平。结果 10 -5mol/L、10 -7mol/L、10 -8mol/L睾酮刺激可促进大鼠血管平滑肌细胞增殖 (3 [H]胸腺嘧啶脱氧核苷掺入法测定分别为 137 6 3± 9 6 9、133 72± 8 81及 198 89± 13 2 9;MTT还原法测定分别为 14 0 5 4± 13 95、14 1 89± 2 0 86及 2 18 92± 11 2 4 ,与对照组相比 ,P <0 0 1) ;10 -7mol/L睾酮 +10 -5mol/L氟他胺能进一步促进血管平滑肌细胞增殖 (3 [H]胸腺嘧啶脱氧核苷掺入法测定为 14 7 91± 11 5 5 ,MTT还原法测定为 175 6 8± 2 6 6 5 ,与对照组相比 ,P <0 0 1;与 10 -7mol/L睾酮相比 ,P <0 0 5 )。 10 -9mol/L～ 10 -5mol/L睾酮刺激组雄激素受体蛋白条带吸光度分别为 14 6 8± 7 6、4 30 9± 2 9 3、184 4± 6 6、14 9 7± 9 3、391 3± 6 0 ;10 -7mol/L睾酮 +10 -5mol/L氟他胺刺激组雄激素受体蛋白条带吸光度为 30 9 6± 2 2 4 ;单?

Objective To investigate the effects of testosterone and its antagonist on the proliferation of vascular smooth muscle cells(VSMCs) and its relation with androgen receptor (AR) expression in those cells. Methods VSMCs were cultured from thoracic aorta of male Sprague-Dawley rats by using the explant method. Effects of testosterone at different concentrations with or without its antagonist flutamide on the proliferation of VSMCs were studied by means of 3[H] thymidine incorporation and MTT method,as well as the expression of androgen receptors by Western blot. Results Testosterone at low concentrations(10 -7 mol/L and 10 -8 mol/L) stimulated proliferation of VSMCs(133.72±8.81 and 198.89± 13.29 respectively for 3[H]thymidine incorporation;141.89±20.86 and 218.92±11.24 respectively for MTT method, P <0.01 versus control),whereas lower and higher concentrations(10 -9 mol/L and 10 -6 mol/L) had no significant effect on the proliferation,and even higher concentration(10 -5 mol/L) had a stimulatory effect(137.63±9.69 and 140.54±13.95 for 3[H] thymidine incorporation and MTT method respectively, P <0.01 versus control).The androgen antagonist flutamide at 10 -5 mol/L did not inhibited the stimulatory effect induced by testosterone at 10 -7 mol/L. AR expression in VSMCs could be up-regulated by testosterone and/or flutamide(146.8±7.6,430.9±29.3,184.4±6.6,149.7±9.3 and 391.3± 6.0 for testosterone concentrations 10 -9 mol/L - 10 -5 mol/L respectively,201.0±14.8 for 10 -5 mol/L flutamide alone, and 309.6±22.4 for 10 -7 mol/L testosterone together with 10 -5 mol/L flutamide group). Conclusion Testosterone modulates proliferation of VSMCs in a dose-related manner,and there is a positive correlation between the stimulation and AR expression in those cells treated with different concentrations of testosterone.