[Regulation of snail heart contractions by neurons of the visceral ganglion].

The system of neurons regulating the frequency and strength of heart beats was studied in the snail subesophageal ganglia. Three out of four neurons exerted a short-term phasic effect on the heart. Stimulation of the V6 neuron led to a prolonged increase in the frequency and strength of the heart beats. Activity of two inhibitory cells (about 1-3/sec) was observed whereas excitatory neurons were silent. All the efferent neurons were involved in parallel and did not affect each other.