人脑局灶性缺血后海马神经元损伤与半胱氨酸蛋白酶-3的关系  

Correlation between neuronal injury and caspase-3 after focal ischemia in human hippocampus

作　　者：戚基萍[1] 王德生[2] 王立峰[1] 吴爱萍[1] 李光伟[1] 陈艳昕[1] 

机构地区：[1]哈尔滨医科大学第一临床医学院病理科,150001 [2]哈尔滨医科大学第一临床医学院神经内科,150001

出　　处：《中华神经科杂志》2005年第2期112-115,共4页Chinese Journal of Neurology

基　　金：国家自然科学基金资助项目(30270480);黑龙江省自然科学基金资助项目(D0203)

摘　　要：目的研究人脑局灶性缺血后海马神经元损伤与凋亡促进因子半胱氨酸蛋白酶-3(caspase-3)之间的关系.方法选取因脑梗死而死亡的尸检脑标本48例,并按缺血时间(发病至死亡的时间)分为8组,选取因其他疾病死亡(无脑缺血)的尸检脑标本6例为对照组;应用HE染色来观察海马CA1区神经元形态变化;应用caspase-3免疫组化染色及caspase-3 mRNA原位杂交来测定人脑缺血后caspase-3的表达情况;用末端脱氧核糖核酸转移酶介导的缺口末端标记(TUNEL)法标记凋亡神经元;用微管相关蛋白-2(MAP-2)的脱失程度反映神经元的受损程度.结果海马CA1区,缺血8 h可检测到caspase-3免疫组化染色的阳性细胞(8.05个/高倍视野),24 h达高峰(24.85个/高倍视野);caspase-3 mRNA原位杂交阳性表达始于4 h(6.75个/高倍视野),16 h达高峰(17.60个/高倍视野);二者均在72 h后呈明显下降趋势.缺血24 h可检测到TUNEL阳性细胞,持续至72 h.MAP-2免疫活性下降早在4 h 即可检测到,之后持续下降,至72 h几乎无阳性表达细胞.72 h前,caspase-3 mRNA在TUNEL染色下与时间成正相关,相关系数为0.721(P<0.05);使用MAP-2时与时间成负相关,相关系数为0.857(P<0.05).4～16 h,受损神经元形态基本正常;24～48 h细胞凋亡特征明显;72 h后,几乎所有神经元形态均呈现严重病理变化.结论人脑局灶性缺血后病灶同侧的海马神经元发生一系列形态学变化,其演变规律与凋亡促进因子caspase-3有密切相关性.Objective To investigate the correlation between the change of ischemic neuronal injury and caspase-3 post-ischemia in human hippocampus.Methods Forty-eight post-mortem specimens from 48 patients, who died of cerebral infarction were observed. According to ischemic time, the 48 specimens were divided into eight groups. Besides, we selected 6 specimens from 6 patients as control, who died of other diseases without cerebral ischemia. Morphological changes were first analyzed by observing hematoxyline/eosin-staining hippocampal sections. The expression of caspase-3 was investigated by using ~in situ hybridization and immunohistochemistry. Terminal deoxynucleotidyl transferase-mediated 2′-deoxyuridine 5′-triphosphate-biotin nick-end labeling (TUNEL) method was performed to clarify the involvement of caspase-3 in neuron death. The loss of microtubule-associated protein 2 (MAP-2) was applied to judge the damaged area and degree of neuronal injury induced by ischemia.Results In the CA1 sector of hippocampus, caspase-3 immunostaining modestly increased at 8 hours (8.05/high-power field, hpf), dramatically increased at 24 hours (24.85/hpf), and decreased somewhat after 72 hours. Caspase-3 mRNA was detectable at 4 hours (6.75/hpf), reached a maximum at 16 hours (17.60/hpf), and faded at 72 hours. TUNEL-positive cells were detectable at 24 hours (10.76/hpf), markedly increased at 48—72 hours. The loss of MAP-2 was obviously detected at 4 hours, progressed significantly between 24 and 72 hours; MAP-2 immunoreactivity was barely detectable at 72 hours. Before 72 hours, the caspase-3 evolution was in parallel with both the up-regulation of TUNEL and the loss of MAP-2. The positive correlation between caspase-3 mRNA and TUNEL was significant at the 0.05 level (correlation coefficient was 0.721); the negative correlation between caspase-3 mRNA and MAP-2 was significant at the 0.05 level (correlation coefficient is 0.857). At the early stage (before 72 hours), the staining of caspase-3 mRNA and immunohistochemistry was pred

关 键 词：脑缺血 神经元 细胞凋亡 半胱氨酸天冬氨酸蛋白酶 微管相关蛋白质类 

分 类 号：R743.3[医药卫生—神经病学与精神病学]