Modification of acetylcholine sensitivity of neuronal membrane by presynaptic stimulation.

The action of electrical stimulation of one of the pallial nerves on the sensitivity of the bursting RPa1 neuron of Helix pomatia to acetylcholine (ACh) was investigated. The depolarizing effect of ACh was significantly decreased by presynaptic stimulation. Stimulation leads also to an attenuation of the ACh-induced increase in membrane conductivity. The effect of stimulation on the ACh evoked response of the membrane was reversibly blocked by cold and was completely eliminated after long term incubation of the neuron under "in vitro" conditions.