大鼠局灶性脑缺血半暗带细胞凋亡动态变化规律的研究

用线栓法制作大鼠大脑中动脉阻塞 (MCAO)模型 ,然后用特异性细胞凋亡检测方法 (TUNEL法 ) ,对局灶缺血后不同时间点的脑组织进行观察。发现MCAO后各时间点局灶缺血范围内被标记的染色阳性的凋亡细胞主要位于局灶性缺血半暗带区 ,而且随着缺血时间的延长 ,凋亡细胞数逐渐增多 (缺血 1、3、6、1 2h分别为 3.6 0± 1 .0 2、1 5 .6 0± 2 .0 6、2 2 .4 0± 1 .85、33.0 0± 2 .83/mm2 ) ,2 4h达到高峰 ( 4 6 .6 0± 3.0 1 /mm2 ) ,4 8h以后明显减少 ( 1 3.6 0±2 .4 7/mm2 ) ,72h以后 ,凋亡表现逐渐消失 ( 5 .0 0± 1 .4 1 /mm2 ) ,各时间点的凋亡细胞数目有显著差异 (P <0 .0 1 ) ;同时两两比较表明除缺血后 1h与 72h,3h与 1 2h及 4 8h外 ,其余各点之间均有显著性差异 (P <0 .0 1 )。假手术组及对侧大脑半球各时间点基本上没有凋亡细胞出现。本研究从细胞凋亡角度重新认识急性缺血性脑血管病治疗的“时间窗” ,为缺血性卒中的治疗提供依据。

Dynamic Changes of Apoptosis Happened in Local Ischemic Penumbra of Rats

In order to observe dynamic change characters of the apoptosis happened in the local ischemic penumbra of rats,models of MCAO(middle cerebral artery obstruction)were made with the thread plugged method. A specific method to test apoptosis named TUNEL method was supplied to observe the ischemia involved brain tissue that happened at different time. Most of the marked positive cells, which were detected at different time, were noticed at local ischemic penumbra areas. The number of apoptosis cells were 3.60±1.02/mm², 15.60±2.06/mm², 22.40±1.85/mm², 33.00±2.83/mm² respectively which were calculated at 1,3,6,12 h after artery obstruction .It reached at 46.60±3.01/mm² 24 h after obstruction and reduced to 13.60±2.47/mm² 48 h later. It gradually disappeared (5.00± 1.41/mm²)after 72 h. The differences above were confirmed by the statistic analyses(P< 0.01).The number of apoptosis increased following the duration after ischemia of brains, it reached at peak value at 24 h later and reduced significantly after 48 h,then, it almost disappeared after 72 h of obstruction.