局灶性脑缺血再灌注损伤神经细胞凋亡的研究

Research on the Nerve Cell Apoptosis Induced by Reperfusion in Rats with Focal Cerebral Ischemia

目的研究局灶性脑缺血再灌注损伤后神经细胞凋亡及其大鼠脑组织不同时间病理学改变情况.方法随机选取66只成年Wistatr大鼠,按照随机数字法分3组,对照组（假手术组,n=6）、观察1组（脑缺血组,n=24）、观察2组（脑缺血再灌注组,n=36）.采用线栓法制造大鼠局灶性脑缺血再灌注模型,手术后HE染色,并分别采用TUNEL法和电镜观察大鼠缺血灌注损伤后神经元凋亡情况和细胞凋亡形态的变化.结果大鼠缺血再灌注后0～63 h时其神经功能损伤最为严重,伴随时间的延长逐渐能得到轻微缓解和改善,再灌注24 h后神经功能明显好转,之后再次出现加重的趋势.研究发现：再灌注后神经元会出现凋亡,TUNEL阳性细胞集中在灌注后病灶中心的边缘区域以及皮层区.结论线栓法制备动物脑组织缺血灌注模型能有效用于脑组织缺血再灌注后的临床分析,局灶区的神经元以凋亡、坏死为主,其中轻度脑缺血主要以神经凋亡为主,中重度缺血主要以坏死为主.

Objective To research the nerve cell apoptosis induced by reperfusion injury in rats with focal cerebral ischemia and the pathological alteration of the brain tissue at different times in rats. Methods The selected 66 adult Wistar rats were randomly divided into three groups,the control group（ sham-operation group,n= 6）,the observation group 1（ cerebral ischemia group,n = 24）,and the observation group 2（ cerebral ischemia reperfusion group,n = 36）. The model rats with focal cerebral ischemia reperfusion were established by suture method. After operation and HE staining,the condition of neuritis apoptosis and the morphological changes of apoptosis were determined by TUNEL method and electron microscope. Results The most serious nerve function deficit appeared during 0 ～ 63 h after ischemia reperfusion in rats,which would slightly relived and improved along with the passage of time. The neurological function improved markedly after 24 h reperfusion,and then appeared the tendency of exacerbation. The research showed that nerve cells would appear apoptosis after reperfusion,the TUNEL positive cells were concentrated at the marginal area and tegument region afterreperfusion. Conclusion The model rats established by suture method are effective for the clinical analysis on cerebral ischemia reperfusion. The major death ways of the nerve cells in focus are apoptosis and necrosis,the primary cause of mild cerebral ischemia is nerve apoptosis,and the primary cause of moderately severe cerebral ischemia is necrosis.