补阳还五汤及其有效部位组方抗脑缺血再灌注损伤的部分机理研究

【作者】 王敏；

【导师】 邓常青； 李文海；

【作者基本信息】 湖南中医学院 ， 中西医结合基础， 2001， 硕士

【摘要】 本实验采用沙土鼠脑缺血再灌注损伤模型，比较研究了补阳还五汤原方和有效部位组方对脑缺血再灌注后海马CA₁区病理形态结构及神经元凋亡、热休克蛋白70（HSP70）表达和反应性星形胶质细胞活化的影响。结果显示： 1、对沙土鼠脑缺血再灌注后海马CA₁区神经细胞病理形态结构的影响：于缺血15分钟再灌注后5天取脑组织观察，发现补阳还五汤及其有效部位组方均可防止脑缺血再灌注后海马CA₁区神经元密度的降低，对海马CA₁区神经细胞病理形态结构变化均有改善作用，且二者作用程度相近，提示补阳还五汤原方和有效部位组方可防止脑缺血后海马CA₁区神经元丢失，对脑缺血后海马CA₁区迟发性神经元损伤有明显的抑制作用。 2、对沙土鼠脑缺血再灌注后海马CA₁区热休克蛋白70表达的影响：脑缺血15分钟再灌注48小时后，脑组织HSP70mRNA和蛋白表达显著增加，补阳还五汤及其有效部位组方可使脑缺血再灌注后HSP70mRNA表达减少，补阳还五汤的抑制作用强于有效部位组方，但两者对脑缺血再灌注后HSP70蛋白的表达增加无明显影响。提示补阳还五汤及其有效部位组方可能通过抗脑缺血作用而抑制了缺血后HSP70mRNA的表达，但两者并不影响HSP70蛋白的表达，这对于缺血后神经元的修复是有益的。 3、对沙土鼠脑缺血再灌注后海马CA₁区神经元凋亡的影响：脑 缺血 15分钟再灌注 48小时后，神经元凋亡指数明显升高，补阳还五 汤原方和有效部位组方均能明显降低海马CAI 区神经元凋亡指数。 提示补阳还五汤原方和有效部位组方可能通过抑制神经元凋亡而对抗 脑缺血的迟发性神经元损伤。 4、对沙土鼠脑缺血再灌注后海马CA；区反应性星形胶质细胞活 化的影响：缺血 15分钟后各组脑组织无 GFAP表达；再灌注 24小时 后，脑组织GFAP表达达高峰（主要在海马区），补阳还五汤及其有 效部位组方可使GFAP表达减弱，二者作用相近；再灌注48小时后， GFAP表达有所下降，而补阳还五汤和有效部位组方 Go表这较模 型组有所增强，二者作用相近。提示星形雕细胞活化主要在脑缺血 后再灌注期，在再灌注早期，补阳还五汤及其有效部位组方通过对抗 缺血性脑损伤而改善星形胶质细胞功能的紊乱，在再灌注后期，则通 过促进星形细胞的活化，有利于缺血损伤的修复。更多还原

【Abstract】 With the living gerbils model of cerebral ischemia reperfusion injury, this research studied the effects of Bu Yang Huan Wu Decoction(BYHWD)and its available compostion combination on pathologic change of neuronal structure in hippocampal gyrus CA1 area, neuronal apoptosis, the expression of heat shock protein70 (HSP7O) and the reactive Astrocyte activation after cerebral ischemia and reperfusion. The results showed: 1. Effect on pathologic change of neuronal structure in hippoccampal gyrus CA1 area: After cerebral ischemia for 15 mm followed. reperfiision for Sd in cerebral tissue, BYI-IWD and its available composition combination have similar effects on increasing the neuronal density and improving the pathological changes in hippocampal CA1 area. The results suggested that BYHWD and its available composition combination could contagonize the loss of the neuron in hippocampal gyms CA1 area and the delayed injury of cerebral tissue after cerebral ischemia. 2. Effect on the expression of HSP7O: After cerebral ischemia for 15 mm lg- followed reperfusion for 48h in cerebral tissue, the level of HSP7O mRNA and protein increased significantly. Both the BYI-IWD and its available composition combination decreased the level of HSP7O mRNA remarkably, the prior is superior to the latter. Neither the BYHWD nor its available composition combination showed any effects on the expression of HSP7O protein. The results suggested that downregulating the expression level of HSP7O mRNA might result in the anti-ischemia effect of BYHWD and its available composition combination, and this is benefit for the repair of the neurons after ischemia. 3. Effect on neuronal apoptosis in hippocanipal gyrus CA1 area: After cerebral ischemia for 15 mm followed reperfusion for 48h, the percentages of neuronal apoptosis increased obviously, both BYHWD and its available composition combination could antagonize neuronal apoptosis. The results suggested that BYHWD and its available composition combination could antagonize the delayed injury of cerebral tissue maybe by antagonizing neuronal apoptosis. 4. Effect on. reactive astrocyte activation after cerebral ischemia: There were no expression of GFAP in cerebral tissue at 15 mm following cerebral ischemia, but the expression of GFAP reached peak after cerebral ischemia for 15 mm followed by reprefusion for 24h, it occurred mainly in hippocampal CA1 area. BYHWD could weaken the expression of GFAP, the effect of its available composition combination was similar to it. Expression if GFAP weakened after cerebral ischerria for 15 mm followed by reperfusion for 48h. Compared with model group, the expression of GFAP strengthened in BYHWD and its available composition combination group, comparable expression of GFAP were observed in both groups. The results suggested that Astrocyte activation occurred mainly during reperfusion after cerebral ischemia. BYHWD and its available composition combination could inhibit activation of astrocyte by antagonizing ischemic injury during early stage of reperfusion, both helped improve the repair of lesion by facilitating astrocyte activation during late stage of reperfusion~更多还原