[The evolution of the synapses in the vertebrate central nervous system (a topical paper)]

The results of comparative morphological and ultrastructural research of the synaptic organization of spinal cord motoneurons from fishes, amphibian, reptiles and mammals are presented in the review. Fundamental regularities of the formation of the synaptic organization of motoneurons in vertebrate phylogenesis were established. The results of electron microscopical analysis showed that all basic elements of the synaptic ultrastructure preserved in the motoneuronal synapse of vertebrates during the evolution. On the basis of large experimental material it was found that the synaptic organization of individual motoneuron as a whole underwent structural reorganization, presented as corresponding transformations in mechanisms of the synaptic transmission.