丹参酮对脂多糖性急性肺损伤大鼠肺组织ACE2表达的影响

目的:探讨血管紧张素转换酶2(ACE2)在脂多糖性急性肺损伤大鼠中的表达变化和作用机制及丹参酮IIA磺酸钠(STS)干预的影响.方法:45只健康雄性Wistar大鼠随机分为正常生理盐水对照组(NS组)、急性肺损伤组(LPS组)、丹参酮IIA磺酸钠干预组(STS组),LPS组和STS组通过股静脉注射LPS(5 mg/kg)建立急性肺损伤模型.STS组在注射LPS前30 min静脉给药10 mg/kg,NS组和LPS组给予等量NS.3组又分为6 h、12 h、24 h 3个时间点亚组,每组5只,检测血气分析、肺组织湿/干重比(W/D)、苏木精-伊红染色、ACE2免疫组织化学表达.结果:与LPS组相比,STS组急性肺损伤的程度明显减轻,PaO2显著改善(P<0.05),肺W/D比值降低(P<0.05),苏木精-伊红染色显示肺组织损伤减轻.免疫组织化学检测ACE2表达明显上升(P<0.05).结论:肺组织中ACE2表达的下降在急性肺损伤的发病机制中起到重要作用,而丹参酮可以改善急性肺损伤大鼠的肺损伤程度,其机制可能与增加ACE2的表达有关.

To study the effect of sodium tanshinone sulphonate IIA on the expression of ACE2 in acute lung injury induced by LPS in rats

Objective：To investigate the expression of ACE2 in acute lung injury（ALI） induced by LPS in rats and to study the effect of sodium tanshinone sulphonate IIA on ALI.Method：Forty-five male Wistar rats were randomly divided into three groups,including control group（NS group）、 acute lung injury group（LPS group）、 sodium tanshinone sulphonate IIA group（STS group）.The rats were intravenously injected with LPS（5 mg/kg） to establish the ALI model.The rats in STS group were treated with STS（10 mg/kg） before LPS,and equivalent volume of normal saline were given to the rats in NS group and LPS group.Arterial blood gas analysis,lung tissue wet/dry weight ratio,lung histopathological changes were observed at 6、12、24 h after ALI was induced.The expressions of ACE2 protein in lung tissues was detected by immunohistochemistry.Result：Compared with LPS group,PaO2 in STS group were significantly increased whereas the ratio of wet/dry weight were decreased（P0.05）.The grading of pathologic damage of lung tissue was attenuated greatly.ACE2 protein expression were significantly higher in STS group than LPS group（P0.05）.Conclusion：Decreasing of ACE2 expression in lung tissue may play an important role in the ALI.STS could attenuate the degree of ALI in rats.The mechanism might be associated with the up-regulation of ACE2 expression.