脑缺血急性期应用促红细胞生成素的抗凋亡作用

Erythropoietin against cell apoptosis in acute phase of cerebral ischemia

目的:探讨促红细胞生成素在脑缺血急性期对神经细胞的抗凋亡作用。方法:实验于2004-04在暨南大学医学院第二附属医院动物实验中心完成。取SD大鼠54只随机分成9组,即假手术组、盐水对照组和促红细胞生成素实验组,其中对照组和实验组大鼠按缺血时间(3,6,12,24h4个时间点)随机分为4亚组。假手术组和每亚组各6只大鼠。各组实验动物采用颈内动脉线栓环扎法建立大鼠局灶脑缺血模型:假手术组线栓只插入9mm,不环扎,不造成阻塞血管情况;促红细胞生成素实验组于栓塞同时给予腹腔注射促红细胞生成素(5000U/kg),盐水对照组给予同体积的生理盐水。观察缺血中心区和边缘区神经细胞形态变化及末端脱氧核苷酸转移酶介导的脱氧三磷酸尿苷缺口末端标记法(TdT-mediateddUTP-biotinnickendlabeling,TUNEL)的表达。结果:盐水对照12,24h组,促红细胞生成素实验24h组各有1只脱失,其余大鼠均纳入结果分析。随缺血时间延长,盐水对照组和促红细胞生成素实验组边缘区TUNEL阳性细胞数均增加,中心区均减少;各时间点促红细胞生成素组的TUNEL阳性细胞数明显少于同时间点盐水对照组,差异有显著性意义(F=12.047,P<0.05)。结论:脑缺血后,中心及边缘区凋亡细胞的增加,应用促红细胞生成素后,中心及边缘区凋亡阳性细胞数明显减少,提示促红细胞生成素对脑缺血急性期的神经细胞具有抗凋亡作用。

AIM: To study the antiapoptosis effect of erythropoietin on neurons in acute phase of cerebral ischemia.METHODS:The experiment was finished in the Center for Experimental Animals,Second Affiliated Hospital, Medical College of Jinan University in April 2004.A total of 54 SD rats were divided randomly into 9 groups: sham operation group,four control groups and four erythropoietin groups(according to the ischemic time,3,6,12 and 24 hours)with 6 rats in each group.The animal models of focal cerebral ischemia were established by nylon suture embolization and cerclage of internal carotid artery.Rats in sham operation group received 9 mm embolization with no cerclage so as not to block blood.Meanwhile,rats in erythropoietin group were injected with erythropoietin(5 000 U/kg) into abdominal cavity,and rats in saline group was injected with the same dose of saline.The changes of neurons in central and marginal area of ischemia were detected, and the number of apoptosis cells were recorded by using TdTmediated dUTPbiotin nick end labeling (TUNEL).RESULTS:One rat was missed in 12 and 24 hours of saline group, and 24 hours of erythropoietin group,respectively. The rest were all involved in the result analysis.The number of TUNEL positive cells increased along with the increased ischemic time in the ischemic marginal area in saline and erythropoietin groups, and decreased in central area,which was less in erythropoietin group as compared with that in saline group,and there was significant difference(P< 0.05).CONCLUSION:The apoptotic cells increased in the ischemic marginal and central area.The positive cells reduce obviously after erythropoietin administration,so erythropoietin may have antiapoptosis effect on neurons in acute phase of cerebral ischemia.