脊髓胶状质突触结构中的生长抑素

SOMATOSTATIN IN SYNAPTIC STRUCTURES OF SUBSTANTIA GELATINOSA OF THE SPINAL CORD

本研究用免疫电镜方法对大白鼠脊髓胶状质内生长抑素的分布进行了观察。超微结构图像表明:含生长抑素的神经纤维末梢参与构成轴体、轴树和轴轴突触的突触前成分。免疫反应产物定位于线粒体外膜、小透亮囊泡周围及大颗粒囊泡内。在免疫反应阳性的终扣内,突触囊泡大多数为圆或卵圆形,少数为扁形。根据超微结构特点结合有关的实验结果,作者认为生长抑素在脊髓胶状质内,很可能是一种神经递质而不是神经调制物。

The distribution of somatostatin(SRIF)in substantia gelatinosa of the rat spinal cord was studied by means of immuno-electron microscopy.The ultrastructural features showed that nerve terminals containing SRIF take part in forming presynap-tie elements of axe-somatic,axe-dendritic and axo-axonic synapses.The immune-reactive products locatl at the external membrane of mitochondria,around the small clear synaptie vesicles and in the large granular vesicles.Most of synaptic vesicles are round or ovoid in shape.Only a few of them are flattened.Based on the ultrastructural characteristics mentioned above and related experimental results the authors believe that SRIF in substantia gelatinosa of the rat spinal cord is probably involved as a neurotransmitter instead of neuromodulator.