糖尿病大鼠海马CA1区超微结构观察

The ultrastructure study on the hippocampus CA1 in diabetic rats

目的观察链脲佐菌素(streptozotocin,STZ)糖尿病大鼠海马CA1区超微结构变化。方法SD雄性大鼠18只随机分为实验组、治疗组及对照组,用STZ复制糖尿病动物模型,饲养12周后测血糖,并进行灌注固定,应用透射电镜观察海马CA1区超微结构。结果电镜下可见糖尿病大鼠海马CA1区神经元细胞核出现核沟,染色质浓缩并聚集;粗面内质网扩张、排列紊乱和脱颗粒;线粒体肿胀,部分空泡变性;髓鞘板层排列疏松,间隙加大,内部轴突神经丝松解、弯曲;突触结构分界不清,突触小泡稀疏。治疗组超微结构与对照组比较无明显病变。结论糖尿病时海马组织出现一系列超微病理改变,为进一步探讨海马结构与糖尿病引发学习和记忆功能障碍的关系提供了形态学依据。

Objective To observe the ultrastructural changes in hippocampus CA1 of diabetic rats. Methods Spragus-Dawley rats were randomly divided into experimental group, treatmental group and control group per group 6 rats. The diabetes rats model were induced by injection of streptozotocin into peritoneal cavity. After 12 weeks, rats were killed for assaying blood sugar and weight, and the submandibular glands uhrastructure were observed with transmission electron microscope（TEM）. Results Experimental group hippocampus of rats neuronal nucleus mainly appear nuclear grooves, chromatin condensation and margination. Rough endoplasmic reticula（RER） exhibited swelling, ribosomal granulesbroke away. Most mitochondria exhibited swelling and vacuole degeneration. Myelin sheath broke up,and synapses degenerated. The ultrastructural of treatment group hippocampus were normal. Conclusion It suggests that the ultrastructral change in hippocampus induced by diabetes and the insulin therapy pro- vides a morphologica evidence for the learning and memory dysfunction.