大黄苷元联合尿激酶动脉溶栓对血栓栓塞性脑缺血大鼠神经细胞凋亡的影响

Influence of Rhubarb Aglycone Associated Thrombolysis on Neurocyte Apoptosis in Rats with Thrombus-occluded Cerebral Ischemia

目的:探讨大黄苷元联合不同时间窗溶栓治疗对脑缺血大鼠神经细胞凋亡的阻抑作用及其对相关调控基因蛋白表达的影响。方法:大鼠随机分为假手术组、模型组、尿激酶溶栓组(简称溶栓组)、大黄苷元组和联合组(大黄苷元+尿激酶组)。大鼠自体血栓结合线栓阻塞大脑中动脉制备血栓栓塞性脑缺血动物模型。大鼠分别于缺血后3,6,9 h经导管由颈内动脉用尿激酶进行溶栓。动脉给尿激酶后24 h,观察大鼠脑组织病理改变;免疫组织化学法检测神经细胞凋亡和凋亡相关基因蛋白Bax,caspase-3和Bcl-2表达。结果:各模型组大鼠病理改变明显,TUNEL细胞增多、Bax和caspase-3表达增强、Bcl-2表达下调;各用药组较模型组TUNEL细胞减少,6 h和9 h组Bax和caspase-3表达减弱、6 h组Bcl-2表达上调;各组9 h分别较其3h的TUNE细胞数增加、Bax增强、Bcl-2减弱;联合组分别较单一用药各时间组TUNEL细胞数减少、6 h和9 h组Bax及caspase-3表达减弱、Bcl-2表达上调。结论:脑缺血可使促凋亡基因Bax表达上调和抑凋亡基因Bcl-2下调,引起神经细胞凋亡,且随缺血时间延长而明显。大黄苷元及尿激酶溶栓可下调Bax,caspase-3,上调Bcl-2表达,对脑缺血神经细胞凋亡有阻抑作用,以二者联合用药的效果尤为理想。

Objective：To compare depression effects of rhubarb aglycone associated thrombolysis using at different time windows through artery on neurocyte apoptosis and its correlated controlling gene in rats with thrombus-occluded cerebral ischemia.Method：Rats were randomly divided into sham-operated,model,urokinase thrombolysis,rhubarb aglycone and associated groups.Rat model of thrombus-occluded cerebral ischemic was duplicated through the occlusion of middle cerebral artery by using the embolus of rat autologous blood blot and being inserted with nylon thread.At the time of 3,6,9 h after the operation of cerebral ischemia,rats were underwenttreatment of thrombolysis by using urokinase through the pipe in internal carotid artery.At 24 h after urokinase thrombolysis,rats brain were taken,and then brain pathological changes were observed.Immunohistochemical method was used to detect the brain neurocyte apoptosis（TUNEL cell number）,and then the expression of Bax,caspase-3 and Bcl-2 were measured in the study.Result：Compared with sham-operated group,pathological changes were obvious,TUNEL cell numbers and expression of Bax,Caspase-3 increased in model group,while expression of Bcl-2 decreased.TUNEL cell numbers in each administration group decreased and expression of Bax,caspase-3 in 6,9 h groups of administration attenuated,while expression of Bcl-2 up regulated in 6 h groups,these changes appeared more significant in 3 h group than that in 9 h group.In comparison with each simple administration group,TUNEL cell numbers in association group reduced,and expression of Bax,caspase-3 in 6,9 h group attenuated,and expression of Bcl-2 up regulated.Conclusion：Up regulation of expression in promoting apoptosis and down regulation of expression in inhibiting apoptosis could be caused by injury of cerebral ischemia and the changes became more obvious following the prolonging of ischemia time.Rhubarb aglycone and thrombolysis could inhibit apoptosis,but effects of their association appeared more significant.Association of rhubarb aglycone and thrombolysis could inhibit apoptosis by up regulating expression of Bax and caspase-3,as well as down regulating expression of Bcl-2.