[Myelinization within the limits of the motor nerve ending as a possible factor in increasing synaptic transmission efficiency].

The end-plate potentials (EPPs) were investigated in frog neuromuscular junctions with different nerve endings structure (cutaneous pectoris muscle). When the muscle fibres input resistance and nerve endings length in selected pairs of synapses were similar, larger EPPs amplitudes were noted in synapses with myelin segments within nerve ending. It is suggested, that myelinization within nerve ending is one of the factors of synaptic efficacy.