[Ultrastructure of sensory endings in sympathetic ganglia].

Ultrastructure of dendrites and their sensory terminals in the cat pre- and para-vertebral ganglia has been studied electron microscopically. There have been found specific organelles, i.e. endoplasmic reticulum of a peculiar shape, laminated bodies, mitochondrial aggregates, etc., which are concentrated in the varicosities and terminals of many long dendrites, thus distinguishing them from the dendrites of efferent (post-ganglionic) neurons. Short processes of ganglionic neurons show clusters of small granule-containing vesicles. The localization and relationship of these terminals with other ganglionic structures has been studied. They are shown to originate from the dendrites of sensory neurons of spinal ganglia, as well as from peripheral autonomic neurons whose cell bodies are located in the sympathetic ganglia mentioned.