Role of cyclic adenosine monophosphate in simple forms of plasticity in the edible snail.

The participation of the adenylate cyclase system in the short-lived changes in the efficiency of synaptic transmission of a functionally identified synapse of the edible snail has been investigated. It was established that imidazole (a phosphodiesterase activator) in a concentration of 5 mM and tolbutamide (an inhibitor of cAMP-dependent phosphorylation) in a concentration of 2 mM do not alter the rate of the depression of EPSPs which is elicited by rhythmic stimulation at a frequency of 0.1 Hz, and do not block heterosynaptic facilitation. At the same time, both of these substances decrease the amplitude of EPSPs. The possibility of the modulation of the efficiency of synaptic transmission through the adenylate cyclase system is discussed.