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凋亡在发育和生理性细胞死亡中起着重要的作用，然而，局灶性或全脑缺血后，神经元的死亡是通过坏死或是凋亡，一直存在争议。本研究采用栓线法建立大脑中动脉缺血再灌流动物模型，成年雄性ＳＤ大鼠缺血０５、１５、３、６ｈｒ，再灌流２４ｈｒ后，用ＴＴＣ、组化染色和ＴＵＮＥＬ方法分别检测梗塞灶体积、细胞形态学改变和核ＤＮＡ降解。神经病学检查按ＺｅａＬｏｎｇａ的五分制评分标准。结果发现除１例无神经缺陷、两例死于癫痫外，其余各组神经缺陷评分均在１～４分之间。ＴＴＣ染色发现在额顶皮质、尾壳核的外侧部以及内侧部的不同范围都有恒定的梗塞灶形成。缺血３０ｍｉｎ时，组化染色未发现明显的病理改变，但有少量ＴＵＮＥＬ阳性细胞夹杂在正常神经元之间。缺血９０ｍｉｎ后，出现神经元皱缩、染色质凝集和凋亡小体形成，并伴有ＴＵＮＥＬ阳性细胞增多。缺血３ｈｒ，额顶皮质ＴＵＮＥＬ阳性细胞和坏死细胞都明显增加。尾壳核内ＴＵＮＥＬ阳性细胞核变形，呈不规则形或短矩形，并有明显的细胞丢失。缺血６ｈｒ，除凋亡细胞和坏死细胞继续增加外，神经元呈现不可逆改变，即核固缩、白质水肿和脑软化。本研究表明大脑中动脉梗塞早期，纹状体和皮质神经元都显示凋亡的形态改变，且前者早于后?
Apoptosis plays an important role in the development and physiological cell death. However, it is controversial whether neuronal death is caused by necrosis or apoptosis after focal or global cerebral ischemia. In this study, we established a rat model of middle cerebral artery occlusion (MCAO) by occlusion. The adult male Sprague-Dawley rats were subjected to 05,15,3,6hr ischemia. After 24hr reperfusion, TTC, TUNEL and TUNEL Infarct volume, cell morphology and nuclear DNA degradation were detected. Neurological examination by ZeaLonga five-point scale. The results showed that in addition to 1 case of neurological defects, two cases died of epilepsy, the remaining group of neurological deficit scores were between 1 to 4 points. TTC staining revealed a constant infarct formation in the different regions of the frontal cortex, the lateral portion of the caudate putamen, and the medial portion. At 30 minutes after ischemia, no obvious pathological changes were observed by histochemical staining, but a few TUNEL positive cells were intercalated between normal neurons. 90min after ischemia, neuronal shrinkage, chromatin condensation and apoptotic body formation, accompanied by increased TUNEL-positive cells. Ischemia 3hr, frontal cortex TUNEL-positive cells and necrotic cells were significantly increased. The TUNEL-positive nucleus in the caudate putamen deforms into an irregular or short rectangle with obvious cell loss. At 6 hours after ischemia, neurons showed irreversible changes except for apoptotic cells and necrotic cells, namely nuclear pyknosis, white matter edema and brain softening. This study shows that in the early middle cerebral artery infarction, the striatum and cortical neurons show morphological changes of apoptosis, and the former is earlier than the latter.