[Structural features of varicose dilatations of vasomotor nerves (according to data from a three dimensional...

Ultrastructure of varicous dilatation of the axons composing small neuronal fasciculi in the sympathetic plexus of the rabbit coronary artery has been studied. According to the data of three dimensional reconstruction, space structure of three neuronal fasciculi has been restorted. Axons of every fasciculus form varicous dilatation at the same area along their course. A lemmocytic process, accompanying the axon as a thin cylinder at the intervaricous part flattens, in the area of varicous dilatations. and embraces all the axons, thus forming a peculiar functional unit of the neuronal fasciculus. From the data obtained and those of literature, it is possible to suggest that not only single axons situating in the nearest approximation to smooth muscle cells, but also single neuronal fasciculi having in their composition axons with varicous dilatation might effectively influence the smooth musculature of the vascular wall.