[Effect of gamma aminobutyric acid on command neurons of Helix lucorum snail neurons].

Studies have been made of the effect of GABA on the activity of identified neurones of the central nervous system of the snail Helix lucorum. GABA perfusion within first 10 min resulted in the increase of reactions to intracellular and transsynaptic stimulation of the neurones studied, depolarization by 3-4 mV being also observed. After this period, further perfusion decreased the spontaneous activity and neuronal reaction, this effect being accompanied by the decrease in membrane resistance. Synaptic and axonal conduction remained unaffected, although cells responded by the action potentials only to strong stimulation. After 30 min of GABA perfusion, tactile stimulation, which in the intact animals induces the avoidance reaction led to opening of the respiratory orifice, i.e. a component of the respiratory cycle.