PM2.5对大鼠血管平滑肌细胞增殖及NO和内皮素分泌的影响

Effect of Particulate Matter 2.5 on the Proliferation and Secretion of NO,ET-1 in Vascular Smooth Muscle Cell of Rats in Vitro

目的研究大气细颗粒物(PM2.5)对大鼠血管平滑肌细胞增殖及NO、内皮素(ET-1)分泌的影响,探讨其可能的作用机制。方法采集湛江市区车流量大、污染较重地区大气中的PM2.5,以0、10、20、50、100、200μg/ml的PM2.5溶液染毒培养SD大鼠血管平滑肌细胞(VSMC)24h。采用噻唑蓝(MTT)法检测PM2.5对VSMC增殖的影响,硝酸还原酶法和RIA法分别检测PM2.5对一氧化氮(NO)、ET-1分泌的影响。结果在10～200μg/ml范围内,随着染毒浓度增加,VSMC的NO水平从(43.53±3.46)μmol/L下降到(29.28±2.28)μmol/L(F=18.89,P<0.01),ET-1水平从(38.06±3.53)ng/L上升到(112.93±15.63)ng/L(F=22.39,P<0.01),MTT值从0.49±0.067增加到0.72±0.025(F=27.89,P<0.01)。结论PM2.5抑制VSMC的NO分泌,增加ET-1分泌,促进体外培养的VSMC增殖,在10～200μg/ml浓度范围内具有剂量依赖性。

Objective To observe the effect of PM2.5 on the secretion of NO, ET-1 and the proliferation of rat vascular smooth muscle cell （VSMC） in vitro. Methods VSMCs were treated with PM2.5 collected from urban area of Zhanjiang, at the doses of 10,20,50,100 and 200 μg/ml. After 24 hours of treatment, the levels of NO and ET-1 in the VSMCs were detected by nitrate reductase method and radioimmunoassay respectively, the proliferation of VSMCs was detected by MTT. Results At the concentrations of 10-200 μg/ml, with PM2.5 increased, the level of NO in VSMCs decreased from （43.53±3.46）μmol/L to （29.28±2.28）μmol/L（F=18.89,P〈0.01）,meanwhile, the level of ET-1 increased from（38.06±3.53）ng/L to （112.93±15.63）ng/L （F=22.39,P〈0.01）,MTT value increased from 0.49±0.067 to 0.72±0.025 （F=27.89,P〈0.01）. Conclusion In VSMC, PM2.5 can inhibite the secretion of NO, promote the secretion of ET-1 and activate cell proliferation in vitro.