大白鼠神经垂体的超微结构及其联系

本文用电子显微镜技术,对大白鼠神经垂体的超微结构进行了研究。结果除证实神经分泌物质在神经末梢内贮存并释放人血液外,还显示在神经分泌末梢之间存在着轴-轴突触样结构;在神经分泌末梢与垂体细胞之间,存在着神经-胶质突触样连接;在垂体细胞之间,存在着中间连接。轴-轴突触和神经-胶质突触样连接的特点是:1.突触前、后膜呈不显著的增厚;2.突触前成分内,有成群的微泡靠近并附着于突触前膜;3.突触间隙为20 nm左右,内含多少不等的电子致密物质。作者认为,以上两种突触样结构和垂体细胞,均与神经分泌物质释放的调节有关。

ULTRASTRUCTURES AND THEIR RELATIONSHIPS OF THE NEUROHYPOPHYSIS IN THE RAT

Ultrastructures of the neurohypophysis in the rats have been studied by means of electron microscopy. Besides identifying the fact that the neurosecretory substances store in the nerve terminals and release into the blood, there are also axo-axonic synaptoid structures existed between neurosecretory terminals and neuro-glial synaptoid contacts between neurosecretory terminals and pituicytes. The characteristics of these contacts mentioned above are as follows: (1) the pre-and postsynaptic membranes are insignificantly thickened; (2) clustered microvesicles are close to and attach to the presynaptic membrane; (3) the synaptic cleft is about 20 nm wide and contains various amount of electron dense materials. The authors suggest that the two kinds of synaptoid structures and pituicytes are all involved in the regulation for the releasing of the neurosecretory substances.