长期远隔后适应对脑缺血再灌注大鼠脑组织神经中丝200表达的影响

摘要

目的 研究长期远隔缺血后适应对大鼠局灶性脑缺血再灌注损伤后脑组织神经中丝200(NF200)表达的影响.方法 应用线栓法制作大鼠大脑中动脉缺血2 h再灌注损伤模型,再灌注即刻给予远端肢体缺血后适应,即双侧股动脉夹闭10 min/放开10 min,反复3次.此后每天给予一次远端肢体缺血后适应.实验分为4组:缺血再灌注7 d组(C7组);缺血再灌注后适应7 d组(P7组);缺血再灌注28 d组(C28组);缺血再灌注后适应28 d组(P28组).每组6只大鼠.采用免疫印迹法研究各组大鼠脑组织中NF200蛋白的表达水平,并采用免疫荧光法观察大鼠脑组织NF200蛋白的表达部位.结果 P7组大鼠脑组织内NF200表达比C7组明显增高(P<0.05),P28组大鼠脑组织内NF200表达比C28组及P7组明显增高(P均<0.05),而C28组大鼠与C7组相比脑组织内NF200表达无明显变化.免疫荧光染色结果显示NF200在神经元胞体及轴突中均有表达.结论 长期远隔缺血后适应可增加大鼠脑组织内NF200的表达,可能与减轻脑缺血损伤相关.%Objective To investigate the effects of remote ischemic post-conditioning on the expression of NF200 in the brain of rats following cerebral ischemia and reperfusion in long term. Methods The focal ischemia and reperfusion rat model was made by suture method. The remote ischemic post-conditioning was performed with occluding of bilateral femoral arteries for 10 mins and reperfusion for 10 mins, repeated for 3 times at the time of reperfusion and then once a day. The rats were divided into 4 groups: the control group at 7 d after cerebral ischemia (C7 , n = 6) , the experiment group at 7 d after cerebral ischemia (the remote ischemic post-conditioning was done everyday after cerebral ischemia, P7, n = 6) , the control group at 28 d after cerebral ischemia(C28, n = 6) , the experiment group at 28 d after cerebral ischemia(the remote ischemic post-conditioning was done everyday after cerebral ischemia, P28, n = 6). The expression of NF200 protein in the brain of rats was determined by Western blotting. The immnnofluorescence was used to detect the localization of NF200. Results The expression level of NF200 in P7 group increased significantly compared with that of C7 group (P<0. 05) ; the expression level of NF200 of P28 group increased significantly compared with that of C28 group(P<0. 05) ; The expression level of NF200 in P28 group increased significantly compared with that of P7 group (P<0. 05) while the expression level of NF200 in C28 group had no significant difference compared with that of C7 group(P>0. 05). Immiinofliienrence staining showed that NF200 expressed both in neuron and axon. Conclusion Remote ischemic post-conditioning in long term increases the expression level of NF200 in the brain of rats, which might be the mechanism of reducing the damage of cerebral ischemia.