大鼠脑缺血再灌流时脑组织病理改变的特点

目的 :观察大鼠脑缺血再灌流时 ,脑组织病理改变的特点和时程。方法 :采用改良的大鼠脑缺血再灌流模型 ,阻塞大脑中动脉 2小时 ,再灌流 0 5～ 48小时 ,TTC和HE染色观察缺血部位、面积 ,神经元渐进性改变的特点。结果 :再灌流 0 5小时有灶性缺血区 ,2 4小时缺血性损伤面积最大 ;6小时内神经元主要为急性期改变即神经元肿胀和浓缩 ;后出现神经元不可逆变性 ,2 4小时形成梗塞区。结论 :本研究结果表明缺血性神经元损伤不仅与缺血的时间、程度且与再灌流时间有关 ,缺血再灌流时神经元经历了可逆变性、不可逆变性和梗塞区形成的变化过程。因此本结果为脑梗塞治疗时间窗的选择提供了参考资料。

THE CHARACTERISTICS OF PATHOLOGICAL CHANGE OF CEREBRAL TISSUE FOLLOWING CEREBRAL ISCHEMA AND REPERFUSION IN RATS

Objectives: To observe the characteristics of neuronal change following cerebral ischemia and reperfusion. Methods: Improved ischemia-reperfusion model in was adopted,After middle cerebral artery was blocked foe 2 hours,then reperfused for 0.5-48 hours. TTC and HE Staining were used to investigate distribution and areas of ischemia and progressive histological features. Result: The ischemic areas (including preoptic area, stratum and cortex) presented at 0.5 hour of reperfusion and peaked at 24 hours of reperfusion. The neurons underwent primarily acute changes (shrinking or swollen) within 6 hours of reperfusion and presented irreversible degeneration after 6hours of reperfusion. At 24 hours, ischemic area in the preoptic area developed into infarcted area. Conclusion: These results show that ischemic injuries of neurons are related not only to the ischemic time and extent but also to the reperfusion time. The neurons suffered a series of changes, including reversible and irreversible degeneration, infarcted maturation. The data of the phasic neuronal changes after ischemia-reperfusion are useful reference materials for selecting the window of therapeutic time to treat cerebral infarction