清热化淤方对脑缺血预处理大鼠ATF4、Caspase-12表达的影响

Effect of Qingre Huayu Prescription on the Expression of Activating Transcription Factor 4 and Caspase-12 after Cerebral Ischemic Preconditioning in Rats

目的观察清热化淤方对脑缺血预处理大鼠缺血再灌注后ATF4、Caspase-12 mRNA及其蛋白表达的影响。方法SD大鼠160只,随机分为假手术组(SO)、脑缺血再灌注组(MCAO)、脑缺血预处理组(BIP)、清热化淤方干预组(QRHY)四组,每组按照再缺血后12h、1d、2d、3d四个时间点分为4个亚组。采用二次线栓法制备大鼠局灶性脑缺血预处理模型,用原位杂交法和Western blot法观察再缺血后各个时间点ATF4、Caspase-12 mRNA及其蛋白的表达变化。结果①MCAO组12h ATF4mRNA及其蛋白表达均达高峰(P<0.01),随再灌注时间延长其表达逐渐下降;BIP组较MCAO组ATF4mRNA及其蛋白表达均明显降低(P<0.05,P<0.01);QRHY组较BIP组进一步降低其表达(P<0.05,P<0.01)。②MCAO组12 h Caspase-12 mRNA及其蛋白表达均达高峰,随再灌注时间延长其表达逐渐下降(P<0.01);BIP组较MCAO组Caspase-12mRNA及其蛋白表达均明显降低(P<0.05,P<0.01);QRHY组较BIP组进一步降低其表达(P<0.05,P<0.01)。结论清热化淤方可通过下调大鼠脑缺血预处理后ATF4、Caspase-12表达发挥其神经保护作用。

Objective To investigate the effect of cerebral ischemic preconditioning （IPC） on the expression of activating transcription factor 4（ATF4） and Caspase - 12 mRNA and protein after focal cerebral ischemia/reperfusion（I/R） in rats. Methods 160 male SD rats were randomly divided into four groups ： sham - operation group, middle cerebral artery occlusion （ MCAO ） group, brain isehemia preconditioning（BIP） group and QRHY group. Each group was further divided into 4 subgroups according to 12h, ld,2d and 3d after L/R. The BIP models were made in order to measure the expression of ATF4 and Caspase - 12 mRNA and protein by in situ hybridization and Western blot. Results The expression of ATF4 and caepase - 12 was mRNA and its protein all increased and reached the peak at 12h （P 〈 0.01 ） ,then was decreased continuously I d later. Compared with MCAO group, IPC could decrease its expression （P 〈 0. 05, P 〈 0.01 ）. QRHYP treatment could further reduce its expression as compared to BIP group（ P 〈 0.05 ）. Conclusion QRHYP can protect neurons through inhibiting the expression of ATF4 and caspase -12 after IPC in rats.