培养的大鼠下丘脑神经细胞衰老发展规律的初步观察

为研究下丘脑神经细胞衰老发展的规律，采用分散细胞培养法，以新生大鼠下丘脑细胞的胞体平均直径、突起长度、数目及电镜下所见的结构变化作为观察指标．把细胞培养期分为静止期、生长期、成熟期和衰老期四个阶段。其中第1周至第6周是培养细胞的主要生长阶段。这期间，细胞形态丰满，突起生长活跃，网络分枝丰富。电镜观察表明培养细胞在3周左右，各种细胞器发育渐趋成熟，并有突触样结构出现。第6周后，突起出现萎缩僵硬，常有串珠样变性，同时胞体进行性增大，线粒体肿胀变性，常有颗粒空泡及电子致密斑块出现，这时细胞进入衰老期。这种分期也同样适于培养的皮层及海马细胞的发育和衰老发展的规律。

THE PRIMARY STUTY OF THE DEVELOPMENT AND AGING PROCESS IN THE CULTURED NEURON OF HYPOTHALAMUS IN RATS

Hypothalarnus is the convergence point of the neuro-endocrine system and also the control center of secreation of growth hormone in pituiary. It maintains an important role in the physiological activity and homeostatosis of the organism.The studies of the aging process in hypothalamus are the intensive focus in the gerontology recently. The life span of cultured neurons of hypothalamus were divided into four periods, such as silent,growth, mature and aging according to the diameterof the cell, length of the neurites and morphlogicalchanges of electrornicroscope in the neonat rats.The vivid period of the cultured neuron is from first week to the sixth week. During these periods the cells were bright, healthy accompanied by the neurites growing actively and branching extentively.Under the electromicroscope, various cellular organ developed maturely and some synapse like structureappeared around 3 weeks in the curtured neuron.After six weeks of culture. the neurons were into the aging period, the neurites became rare. tough.and atrophy and the cell size increased gradually. Inthe same time, the mitochondria were swollen and degenerative. and there were some varicosities anddense electronic granule within the cells. These resuits were as same as those of the cultured neuron inthe hippocampass and cortex described by some other authors.