参芎注射液对大鼠脑缺血再灌注后内质网应激相关分子C／EBP同源蛋白表达的影响

The effects of shenxiong injection on the expression of the endoplasmic reticulum stress associatedmolecules CHOP following cerebral ischemia-reperfusion injury in rats

【摘要】目的检测内质网相关分子C／EBP同源蛋白（C／EBPhomologyprotein，CHOP）在缺血再灌注大鼠脑内的表达变化及参芎注射液对CHOP的影响，以期为参芎注射液的脑保护作用提供理论依据。方法144只雄性SD大鼠按随机数字表法分为三组：假手术组、手术组、参芎组。采用线栓法制作大脑中动脉缺血再灌注模型，分别于再灌注后6、12、24、72h时相点处死动物，用免疫组化学及逆转录聚合酶链反应法分别检测脑缺血区CHOP蛋白水平及mRNA水平；末端标记法原位检测神经细胞凋亡。结果CHOPmRNA及蛋白水平在再灌注后均有升高，分别在再灌注后12、24h时相点达到高峰；在缺血再灌注模型中，神经细胞凋亡的数量随再灌注时间延长而增加，24h时相点到达高峰；在再灌注后各个时间点参芎干预组凋亡细胞数均低于手术组（P〈0．01）；再灌注后6、12、24、72h参芎干预组CHOPmRNA及蛋白水平明显低于相应时间点的手术组大鼠（P〈0．01）。结论参芎注射液可能通过抑制脑缺血再灌注后内质网应激诱导的CHOP的表达进而减少神经细胞凋亡，发挥神经保护作用。

[ Abstract] Objective To investigate the expression of C/EBP homology protein （CHOP） in rat brain tissue after focal cerebral ischemia-reperfusion, as well as to observe the influence of the shenxiong in- jection on the expression of CHOP. Methods One hundred forty four male rats were randomly divided into three groups： the sham-operation group, operation group, sbenxiong group. Focal cerebral ischemia and reperfusion rat models were established by using suture. Zea Longa method was introduced to evaluate neu- rologic behavioral changes. The levels of mRNA and protein of CHOP were measured with methods of immu- nohistochemistry and reverse transcription polymerase chain reaction. The neuronal apoptosis was detected by the method of terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick end labeling. Results The expression of CHOP was up-regulated in per-infarction after cerebral ischemia-reperfusion in rats. CHOP mRNA and protein levels peaked at the 12th h and 24th h after reperfusion, respectively. The apop- tosis cell counting increased gradually after cerebral ischemia-reperfusion and peaked at the 24th h after reperfusion. Compared with the saline control group, treatment with shenxiong injection could reduce the neuronal apoptosis at the 6th, 12th, 24th, and 72nd h after reperfusion （ P 〈 0. 01 ）. Compared with the saline control group, treatment with shenxiong injection could decrease CHOP mRNA and protein expression at the 6th, 12th, 24th, and 72nd h after reperfusion （ P 〈 0. 01 ）. Conclusions Shenxiong Injection may prevent neurocyte from apoptosis by inhibition of the expression of CHOP induced by endoplasmic reticulum stress.