[Ultrastructure of heart synapses].

The nerve endings in the intramural ganglia of the rat's heart are connected by synaptic and non-synaptic junctions with the dendrites and neuron bodies. Peri-membrane indurations of synaptic complexes may look relatively symmetrical or asymmetrical depending on the orientation of the section in relation to the elements of the Akert's presynaptic lattice. In non-synaptic junctions the indurations are symmetrical, but the presynaptic one may be more complicated in its structure. The synaptic complexes are disposed in the field of synaptic dilatations of axons and in the sites of interlacing thin "preterminal" parts of axons with dendrites. They connect preganglionic fibres with dendrites, neuron bodies and with the filamentous and fungiform thorns.