不同低氧时间诱导的大鼠肺动脉平滑肌细胞miR-199a表达的动态变化

The expression changes of miR-199a in hypoxic-induced pulmonary artery smooth muscle cells of rats

目的 观察并分析microRNA-199a（miR-199a）在不同低氧时间诱导的大鼠肺动脉平滑肌细胞（PASMCs）中表达的变化,为探讨miR-199a对PASMCs增殖的调控作用及机制奠定基础.方法 原代培养的PASMCs分别于常氧和低氧下培养6h、12 h、24 h和48 h,采用四甲基偶氮唑蓝比色法（MTT）检测各组细胞增殖情况,实时荧光定量PCR检测各组细胞miR-199a的表达情况.结果 ①MTT检测结果显示低氧组各时间点PASMCs吸光度（A值）均显著高于相对应的常氧组（P＜0.05）;②低氧组PASMCs的miR-199a表达随时间的延长呈持续降低趋势,N48 h组、H6 h组、H12 h组、H24 h组、H48 h组的PASMCs的miR-199a表达量分别为5.55±0.52、4.73±0.25、3.41±0.38、1.32±0.07、0.84±0.16.与N48 h组比较,H6 h组、H12 h组、H24 h组、H48 h组PASMCs miR-199a的表达均显著下降（P值均＜0.05）;除低氧48 h组与低氧24 h组比较,miR-199a的表达差异无统计学意义（P =0.10）外,其余各组之间PASMCs miR-199a的表达差异均有统计学意义（P值均＜0.05）.结论 低氧诱导后miR-199a在PASMCs中的表达下调,且随着低氧时间的延长,miR-199a的表达有降低的趋势,推测其可能参与了低氧诱导的PASMCs增殖的调控.

Objective To observe and analysis the changes of microRNA-199a （miR-199a） expression in rat pulmonary artery smooth muscle cells （PASMCs） induced by different hypoxia time,and lay the foundation to explore the effect and mechanism of regulation of miR-199a on PASMCs proliferation.Methods The primary cultured PASMCs respectively cultured under normoxic and hypoxic 6 h,12 h,24 h,48 h,using methyl thiazolyl tetrazolium colorimetric （MTT） detection of cell proliferation,real-time quantitative PCR detection of miR-199a expression in each group PASMCs.Results ① MTT test results showed that the PASMCs absorbance （A value） of the hypoxic group at each time point is significantly higher than the corresponding normoxic group （P 〈0.05）.② The expression of miR-199a in hypoxia group PASMCs was sustained with time decreased apart from hypoxic hypoxia 24 h group compared the expression of miR-199a 48 h group was no significant difference （P =0.10）,the expression of miR-199a among other groups PASMCs was significantly different （P 〈 0.05）.The expression quantity of miR-199a of N48 h group,H6 h group,H12 h group,H24 h group,H48 h group is 5.55±0.52,4.73±0.25,3.41±0.38,1.32±0.07,0.84 ± 0.16,respectively.Conclusions The expression of miR-199a in PASMCs decreases after induction of hypoxia.We speculated that miR-199a may be involved in the regulation of hypoxia-induced PASMCs proliferation.