[Protein-synthesis blockers reproduce the effect of nociceptive sensitization on the defense and food reactions in the snail].

Effects of translation inhibitors on defence and feeding behaviour and command neurons of defence behaviour (L-RPl1) were studied in Helix lucorum snail. It was found that anisomycin and cycloheximide facilitated defence reactions and neuronal responses evoked by tactile or chemical stimuli 60-80 min after inhibitor application. At the same time feeding behaviour and neuronal responses (L-RMtc1 neurons) evoked by a food stimulus were suppressed. Effects of inhibitors were obtained within 30 min of their application or single injection in intact snail. Effects of inhibitors were absent after continuous application or double injection with 50 min interval. Duration of the inhibitor effects depended on modality of a sensory stimulus. In particular, inhibitor effects on behavioural and neuronal responses evoked by tactile stimuli lasted 1 h., by weak quinine solution--2-3 h., and by a food stimulus--1.5 h. Cycloheximide suppressed only appetitive phase of feeding behaviour but did not affect consummatory phase of feeding behavior. Some parameters of the behavioural and neuronal effects were similar to those obtained during sensitization development. It was suggested that translation inhibitors induced activation of synthesis of protein molecules with a short lifetime, functions of which consisted in selective regulation of synaptic transmission.