兔脑缺血再灌注后细胞凋亡与TIMP-1表达的特点

目的 探讨兔脑缺血再灌注后细胞凋亡和基质金属蛋白酶抑制因子-1（TIMP-1）表达的特点.方法 成年健康新西兰兔103只,应用线栓法建立大脑中动脉闭塞（MCAO）动物模型,将成功的60只兔MCAO模型随机分为永久性缺血组和缺血再灌注组,各30只.原位末端标记法检测两组脑组织细胞凋亡的情况,免疫组织化学方法检测脑组织TIMP-1表达的情况.结果 脑缺血后脑组织细胞凋亡数逐渐增多,缺血12 h达高峰,以后逐渐减少（F=14.48,q=4.79～9.39,P〈0.01）.缺血1 h时脑组织TIMP-1阳性细胞数逐渐增多,48 h达高峰（F=52.05,q=4.98～19.43,P〈0.01）.动物缺血1 h再灌注后,各时间点凋亡细胞数和TIMP-1表达都低于永久性缺血组,再灌注23 h阳性细胞数最多,再灌注47 h下降（F=8.34、53.34,q=3.10～18.70,P〈0.01）.结论 急性脑缺血再灌注后,细胞凋亡与TIMP-1表达一致.

CHARACTERISTICS OF APOPTOSIS AND TIMP-1 EXPRESSION IN RABBITS AFTER CEREBRAL ISCHEMIA AND REPERFUSION

Objective To study the characteristics of apoptosis and expression of tissue inhibitor of metalloproteinase-1 （TIMP-1） in rabbits after cerebral ischemia and reperfusion. Methods A total of 103 adult healthy New Zealand rabbits were used for the study. A model of middle cerebral artery occlusion （MCAO） was successfully created in 60 rabbits with filament liga- tion method, which were equally randomized to permanent ischemia （PI） group and ischemia-reperfusion （IR） group. The tissue apoptosis was determined with TUNEL assay and immunohistochemisty used to tdetect the expression of TIMP-1 in cerebral tis- sue. Results After cerebral ischemia, the number of apoptotic cells increased gradually and reached the peak at 12 h, and then the number began to decrease gradually （F=14.48,q=4.79-9.39,P〈0.01）. The expression of TIMP-1 enhanced 1 h after ischemia, reaching the peak at 48 h （F=52.05,q=4.98-19.43,P〈0.01）. The number of cell apoptosis （F=8.34,q=3.10-7.36,P〈0.01） and TIMP-1 expression （F=53.34,q=6.47-18.70,P〈0.01） in those reperfusion after ischemia for 1 h were significantly lower at all time points than that in PI group. The number of ceils reached the greatest level 23 h after reperfusion, and then began to decrease at 47 h. Conclusion The expression of TIMP-1 was in accordance with cell apoptosis after acute ischemia-reperfusion.