缺氧对大鼠心脏N-甲基-D-天冬氨酸受体亚单位1表达水平的调控

Effect of hypoxia on expression of N-methyl-D aspartate receptor subunit 1 mRNA in heart of rats

目的探讨缺氧对大鼠心脏N-甲基-D-天冬氨酸受体亚单位1(N-methyl-D-aspartate receptor subunit1,NR1)mRNA表达水平的调控。方法雄性SD大鼠12只按照随机数字表法分为对照组(Con组)和循环间歇缺氧(cyclic intermittent hypoxia,CIH)组,每组6只,CIH组给予CIH处理,Con组给予空气模拟缺氧过程,3周后,分离大鼠心脏,通过RT-PCR检测心脏NR1mRNA表达水平。另将大鼠心肌细胞H9C2随机分为4组,为缺氧0h组、1h组、3h组和6h组,RT-PCR检测各组细胞NR1 mRNA表达水平。结果CIH组和Con组大鼠心脏NR1mRNA分别为143.65±3.74、53.01±10.52,2组比较差异有统计学意义(P<0.05)。H9C2细胞缺氧0h组、1h组、3h组和6h组NR1mRNA分别为18.98±3.73、24.16±6.17、243.68±16.03和113.17±6.51,3h组和6h组NR1mRNA表达较0h组和1h组明显升高,差异有统计学意义(P<0.05)。结论缺氧诱导心脏NR1mRNA表达水平上调,参与调节心肌对缺氧的反应。

Objective To study the effect of hypoxia on expression of N-methyl D-aspartate recep-tot 1 （NR1） mRNA responsed to cyclic in termittern hypoxia （CIH, 10 % O2,12 times/h per8h for 21 days） in heart of rats or persistent hypoxia （1% O2,5% CO2,94% N2） in H9C2 cells. Methods Twelve adult male SD rats were divided into control group （n=6） and CIH group （n： 6）. Rats underwent CIH at a rate of 12 cycles/h for 8 h/d for 21 days in Oxycycler A84 Hypoxia Chamber, those in control group were exposed to air instead of hypoxia. In a separate experiment, H9C2 cells were exposed to hypoxia for 0 h,1 h,3 h and 6 h ,respectively. After exposed,in the left ventricles of the rat hearts and H9C2 cells,NR1 mRNA expression was detected by RT-PCR. Results In the heart of rats,the expression level of NR1 mRNA was 143.65±3.74 in CIH group and 53.01±10.52 in control group （P〈0.05）. In the H9C2 cells, the expression level of NR1 mRNA was 18.98±3.73 in 0 h hypoxia group,24.16±6.17 in 1 h hypoxia group,243.68±16.03 in 3 h hypoxia group,and 113.17±6.51 in 6 h hypoxia group,and was significantly higher in 3 h hypoxia group than in the other 3 hypoxia groups （P〈0.05）. Conclusion Hypoxia upregulates the NR1 mRNA expression in heart of rats and regulates their response of myocardium to hypoxia.