大鼠缺氧过程中脑线粒体超微结构变化及形态计量学研究

ULTRASTRUCTUER CHANGE AND QUANTITATIVE ANALYSIS OF CEREBRAL CORTEX MITOCHONDRIA IN RATS EXPOSED TO HYPOXIA

目的 :观察及定量分析急、慢性缺氧后大鼠脑线粒体形态变化。方法 :动物分别在低压舱内模拟 40 0 0m高原连续缺氧 3天和 40天后 ,取大脑皮质组织 ,作超薄切片后透射电镜观察 ,图像经计算机扫描后做生物体视学测量。结果 :急性缺氧线粒体体积增大 ,部分出现嵴紊乱、嵴肿胀 ,线粒体平均直径、截面积增大 ,比表面积减小 (P <0 .0 5 )。慢性缺氧后线粒体形态及体积密度与面数密度未见显著变化 (P >0 .0 5 ) ,与急性缺氧组比较 ,线粒体平均直径、截面积减少 (P <0 .0 5 )。结论 :急性缺氧时线粒体以出现肿胀等形态损伤为主要特征 ,而慢性缺氧可使这种形态损伤得到恢复 ,同时没有观察到脑皮质线粒体数目有显著改变。

To observe and quantitatively analyse morphologic changes of cerebral cortex mitochondria from rats exposed to acute and chronic hypoxia.Methods:Animals exposed to 4 000m simulated high altitude in a hypobaric chamber.Pieces of cerebral cortex were taken from the animals after threedays and forty days hypoia exposure and ultrathin section were made.Observation by electron microscope and quantitatively analyse in biogenetic sterelolgy by electron micrographs.Results:Mitochondria mass increased in acute continous three-day hypoxia group.Some mitochondriar cristae were disordered and swollen.Meanwhile mitochondrial average diameter and average area increased but spcific surface decreased after animals exposed to acute hypoxia.No observable changes in mitochondrial morphology and numerical density were found during chronic hypoxia(P>0.05).Compared with acute hypoxia group,the average diameter and average area beceased(P<0.05).Conclusions:The results suggested that acute hypoxia can cause mitochondrial swelling and other damage of morphlology and recover in chronic hypoxia.No changs observed in the number of mitochondria in rat cerebral cortex during hypoxia.