目的·探讨载脂蛋白E（ApoE）基因敲除（KO）小鼠肾脏caspase信号和凋亡水平的改变以及重组血管紧张素转换酶2（ACE2）干预治疗对其的影响。方法·采用11～12周龄的ApoEKO小鼠，每日经微泵输入1.5 mg/kg血管紧张素Ⅱ（Ang Ⅱ）和/或2 mg/kg重组人ACE2（rhACE2）治疗，为期2周。分别采用蛋白质印迹法和TUNEL法检测小鼠肾脏组织中细胞凋亡及相关信号改变。结果·与野生型对照组相比，ApoEKO小鼠肾脏细胞凋亡水平升高。Ang Ⅱ输入后促使ApoEKO小鼠收缩压水平升高，肾脏细胞凋亡水平、活化型caspase-3和caspase-8表达以及血浆尿素氮与肌酐水平均明显升高，上述作用可被重组ACE2干预所逆转。结论·重组ACE2治疗在降低Ang Ⅱ输入的ApoEKO小鼠血压水平的同时，可明显改善肾脏细胞凋亡和肾功能，提示ACE2对动脉粥样硬化性肾脏损伤具有一定的功效。

Objective · To investigate the alterations in renal caspase signaling and apoptosis in apolipoprotein E (ApoE)-knockout (KO) mice and the effects of recombinant angiotensin-converting enzyme 2 (rACE2) on these alterations. Methods · The ApoEKO mice aged 11- or 12-week were infused with 1.5 mg/kg of Ang Ⅱ and/or 2 mg/kg of recombinant ACE2 (rACE2) per day for 2 weeks. Alterations in renal caspase signaling and renal cell apoptosis were determined with Western blotting and TUNEL method, respectively. Results · The renal cell apoptosis level was elevated in the ApoEKO mice as compared with the wild-type controls. Ang Ⅱ infusion promoted the increases in systolic blood pressure, renal cell apoptosis, expressions of cleaved caspase-3 and cleaved caspase-8, and levels of plasma urea nitrogen and creatinine, which could be revered by rACE2 intervention. Conclusion · The rACE2 treatment can lower the elevated blood pressure induced by Ang Ⅱ in ApoEKO mice and significantly improve renal cell apoptosis and kidney function, which suggest that ACE2 has certain protective effect on atherosclerotic renal injury.