脑缺血大鼠海马超微结构的形态定量研究

对大鼠双侧颈总动脉夹闭2小时,经透射电镜观察海马,用Weibel氏形态定量法分别测量了海马1区和3区的线粒体和突触的表面积密度(Svi)、表面积—体积比(Si/Vi),并与对照组进行了比较。结果表明:缺血时海马1区受损较严重,表现为线粒体体积缩小,数量减少,Svi下降;突触数量有增多的趋势,但突触的Svi与Si/Vi变化不明显。缺血组海马3区受损较轻,线粒体和突触的结构基本正常,其Svi、Si/Vi与对照组差别不显著,提示了3区对缺血有较强的耐受性。

MORPHOMETRICAL RESEARCH OF THE ULTRASTRUCTURE OF THE HIPPOCAMPUS AFTER CEREBRAL ISCHEMIA IN THE RAT

Both carotid arteries of the rat were occluded with clips for 120 minutes. Ultrastructure of the CA1 and CA3 regions of the hippocampus was observed by transmission electron microscope. The Surface Density (Svi) and the Surface-to-Volume Ratio (Si/Vi) of the mitochondria and synapses in CA1 and CA3 regions were measured by means of Weibel's morphometrical techniques. The results indicated that the damage of the CA1 was serious in ischemia group. The volume and number of the mitochondria were reduced and Svi decreased. The number of the synapses in ischemia group showed atendency to increase. The damage of the CA3 was slight. The structure of the mitochon dria and synapses were generally normal. The Svi arid Si/Vi of CA3 showed no significant difference as compared to that of the control group. The results suggested that the CA3 region might be more resistant to ischemia.