大鼠蓝斑的老年性变化——细胞计数和超微结构观察

AGING CHANGES OF LOCUS COERULEUS IN RAT:NEURON COUNTS AND ULTRASTRUCTURES

用雄性Wistar大鼠,老年组(33个月)7只,青年组(6.5个月)9只。左侧蓝斑作常规电镜观察,右侧蓝斑经克紫染色后在光镜下作细胞计数。结果是老年组神经元数比青年组少,(P<0.01)。电镜下,老年大鼠蓝斑有不少神经元出现变性现象,如胞浆内尼氏体消失,粗面内质网减少,线粒体嵴断裂,神经色素增多,胞核皱缩。许多小树突萎缩,空泡化,部分有髓轴突和终末发生溃变,而且还出现少量的老年斑,胶质细胞明显增生。

Two groups of male Wistar rats were used,one aged 33 months old,the other 6.5 months.The left Locus coeruleus were observed under EM and the neuron numbers of the right were counted under LM by Nissl stain.The neuaons showed a decrease in number in old rats,P<0.01 Under EM,some aging neurcns showed degenerated changes:less of Nissl substances,decline of rough endoplasmic reticulums,break-up of the crest of mitochondria,increase cf neuromelanins and shrinkage of cell nucleus etc.There were also a lot of vacuolated and diminished small dendrits,some degenerated neuroaxons and terminals,a few senile plaques and an increase of glial cells in Locus coeruleus of aged rats.