脂多糖对大鼠肺微血管内皮细胞ACE和ACE2表达的影响及血管紧张素转换酶抑制剂的干预作用

Effects of lipolysaccharide on expression of ACE and ACE2 in rat pulmonary microvascular endothelial cells and intervention effects of angiotensinconverting enzyme inhibitor

目的观察脂多糖(LPS)对大鼠肺微血管内皮细胞(PMVECs)血管紧张素转换酶(ACE)和血管紧张素转换酶2(ACE2)表达的影响及血管紧张素转换酶抑制剂(ACEI)Captopril的干预作用。方法组织块法体外培养大鼠PMVECs,观察LPS对PMVECs作用的时间和浓度相关毒性以及Captopril的干预作用;再将PMVECs随机分为4组:对照组(n=6),不加干预措施;Captopril组(n=6),10-5mol/L Captopril孵育细胞8 h;LPS组(n=6),1 mg/mL LPS孵育细胞8 h;Captoril+LPS组(n=6),10-5 mol/L Captopril孵育细胞30 min后再加入1 mg/mL LPS孵育8 h。CCK8检测细胞活性;Western blotting法检测各组细胞ACE和ACE2的表达。结果 LPS可对大鼠PMECs产生明显的毒性作用,并可使细胞ACE表达上调及ACE2表达下降;经Captopril干预后,可明显抑制LPS的细胞毒性作用,并逆转LPS对PMVECs中ACE及ACE2表达的影响,使ACE和ACE2表达水平回调至对照组水平。结论 ACEI能减轻LPS所致的PMVECs毒性作用,而ACE及ACE2表达的变化可能在这一过程中起重要作用。

Objective To investigate the effects of lipolysaccharide（LPS） on expression of angiotensin-converting enzyme（ACE） and angiotensin-converting enzyme 2（ACE2） in rat pulmonary microvascular endothelial cells（PMVECs） and the intervention effects of angiotensin-converting enzyme inhibitor（ACEI） Captopril.Methods Rat PMVECs were cultured in vitro with tissue explants adherant method,the toxic effects of LPS on PMVECs were investigated by treatment of PMVECs with different concentrations of LPS for different time,and the intervention effects of Captopril were observed.PMVECs were randomly divided into control group（without intervention,n=6）,Captopril group（treatment with 10-5 mol/L Captopril for 8 h,n=6）,LPS group（treatment with 1 mg/mL LPS for 8 h,n=6） and Captoril＋LPS group（treatment with 10-5 mol/L Captopril for 30 min and 1 mg/mL LPS for 8 h,n=6）.Cell viability was determined by CCK8,and the expression of ACE and ACE2 in each group was detected by Western blotting.Results LPS had significant toxic effect on rat PMECs,increased the expression of ACE,decreased the expression of ACE2.Captopril significantly inhibited the toxic effects of LPS,reversed the expression of ACE and ACE2,and regulated the level of ACE and ACE2 to the level of control group.Conclusion ACEI could attenuate the toxic effects of LPS on PMVECs,and the expression of ACE and ACE2 may be involved in the mechanism.