中文摘要：

目的研究乙醛脱氢酶2（ALDH2）介导乙醇预处理减轻小鼠肾小管上皮细胞（TEC）缺血再灌注（IR）损伤的作用。方法取C57BL／6J小鼠的TEC，进行原代培养。小鼠TEC经乙醇预处理3h后，建立体外模拟IR的模型，检测细胞的乳酸脱氢酶（LDH）漏出率，观察乙醇预处理减轻TEC的IR损伤的作用。采用已构建的ALDH2的小干扰RNA（ALDH2-siRNA）转染TEC，转染48h后采用蛋白质印迹法验证ALDH2蛋白的变化情况，检测ALDH酶活性的改变，然后进行乙醇预处理和模拟IR操作，最后检测TEC的LDH漏出率，分析ALDH2在乙醇预处理减轻TEC的IR损伤中的作用。结果乙醇预处理显著降低了IR后小鼠TEC的LDH漏出率，验证了乙醇预处理减轻小鼠TEC的IR损伤的作用；转染ALDH2-siRNA后，TEC的ALDH2蛋白．含量下降82．1％，ALDH酶活性下降了67．3％。在下调ALDH2表达之后，乙醇预处理减轻TEC的IR损伤的作用几乎消失。结论乙醇预处理可以减轻小鼠TEC的IR损伤，ALDH2酶在此效应中发挥了重要作用。

英文摘要：

Objective To investigate the role of aldehyde dehydrogenase 2 （ALDH2） in the protection against tubular epithelial cells （TEC） ischemia/reperfusion （IR） injury induced by pretreatment with ethanol. Methods Mouse primary cultured TECs were pretreated with 50 mM ethanol 3 h before simulation of in vitro IR. Lactate dehydrogenase （LDH） release was assessed to evaluate the protection of ethanol pretreatment on IR injury. Thereafter, TECs were transfected with a negative control siRNA （NC） or an ALDH2-siRNA. The ALDH2 protein levels and ALDH enzymatic activities were assessed 48 h after transfection. Ethanol pretreatment and in vitro IR were performed on those transfected TECs. LDH release was assessed to evaluate the role of ALDH2 in the ethanol pretreatment-induced protection against IR injury. Results Ethanol pretreatment significantly reduced the LDH release in TECs upon IR insult. As compared with NC group and INTERFERin group, the ALDH2 protein levels were decreased by 82. 1%, ALDH enzymatic activities were decreased by 67. 30%, and the protective effect induced by ethanol pretreatment was almost completely abrogated in ALDH2-siRNA group. Conclusion Ethanol pretreatment protects TECs against IR injury through ALDH2 dependent pathways.