[Differences in the responses of identified neurons to chemical stimuli in satiated and hungry edible snails].

Reactions of command neurones for avoidance behaviour to food were investigated in hungry and satiated snails in "CNS-chemoreceptor" preparations, in which hemolymph was washed out by saline. Neuronal responses in hungry animal preparations differed significantly from responses in satiated animals preparations. Perfusion of hungry animal preparations with hemolymph of satiated animals changed significantly the responses of command neurones for avoidance behaviour. These responses resembled the reactions of the same neurones to food after aversive conditioning to food of hungry snails. The role of humoral factor in learning is discussed.