老年大鼠垂体神经叶分泌纤维的电镜观察

ELECTRON MICROSCOPIC OBSERVATION OF NEUROSECRETORY FIBRES OF HYPOPHYSEAL NEURAL LOBES IN AGED RATS

透射电镜观察青年组(3～6月)和老年组(18～30月)雄性大鼠的垂体神经叶、发现老年大鼠的神经膨大中神经分泌颗粒随增龄减少显著,而分散的微泡和空泡相对较多.退化、变性的神经膨大增多.轴一轴突触样结构缺乏.细胞间隙增宽.根据超微结构特征将神经膨大划分五型,并就各型神经膨大的随龄变化进行讨论.

The hypophyseal neural lobes of young adult (3-6 months) and aged (18-30 months) male Wistar rats were observed with TEM. The principal findings were as follows: neurosecretory gran-ules (NSG) decreased significantly with age in the nerve swellings of senescent rats and increased in their dispersed microvesicles and vesicles. There was a significant increase of degenerated and deteriorated swellings and lack of synaptic contacts among the axon terminals. The intercellular space around the nerve swellings expanded in the process of aging. In this paper we classify nerve swellings of the hypophyseal neural lobes into five types according to their different ultrastructural features and discuss their changes with age.