醛固酮诱导大鼠主动脉平滑肌细胞凋亡

Aldosterone induces aortic smooth muscle cell apoptosis

目的观察醛固酮在体内能否诱导主动脉平滑肌细胞凋亡。方法将24只SD大鼠随机分为3组，每组8只：（1）空白溶剂设为对照组；（2）醛固酮组；（3）醛固酮＋血管扩张剂组。渗透泵内分别注入醛固酮（1μg／h）或空白溶剂，然后埋于大鼠背部皮下。肼苯哒嗪[25mg／（kg·d）]溶于引用水，每13灌胃1次。8周后脱氧核苷酸末端转移介导的缺口末端标记法（TUNEL）检测凋亡的主动脉平滑肌细胞。结果醛固酮组和醛固酮＋血管扩张剂组大鼠主动脉TUNEL阳性的平滑肌细胞分别占（18．0±1．5）％和（16．5±2．0）％，与对照组（4．7±1．0）％比较，差异有统计学意义（P〈0．05）；后两组之间差异无统计学意义（P〉0．05）。结论醛固酮在体内可以直接诱导主动脉平滑肌细胞凋亡。

Objective To determine whether aldostemne induces aortic smooth muscle cell apop- tosis/n vivo. Methods 24 Sprague-Dawley rats were randomly divided into 3 groups： vehicle as control; aldosterone and aldosterone plus hydralazine. All animals were then implanted with an osmotic mini-pump containing either aldosterone （1 μg/h） or vehicle. Hydralazine [ 25 mg/（ kg. d） ] was resolved in drinking water and garaged once daily. After 8 weeks, aortic smooth muscle ceil （ASMC） apoptosis was examined by terminal-deoxynuclootidyl tranderase mediated nick end labeling （TUNEL） assay. Results TUNEL- positive aortic smooth muscle cells in aldosterone-infused and aldosterene plus hydralazine rats were （ 18.0 ± 1.5 ） % and （ 16. 5 ± 2. 0） % respectively; compared with control rats （ 4. 7± 1.0 ） %, there was signifi- cant difference （P 〈 0. 05 ）. In contrast, no significant difference was achieved between the latter two groups （P 〉 0. 05）. Conclusion This study＇ s findings suggest that aldosterone induces aortic smooth muscle cell apoptosis by its direct effect on the aorta.