It was found that nociceptive sensitization was followed by long-term facilitation of synaptic responses evoked by chemical sensory stimulation of the snail "head", tactile stimulation of the snail "head" and foot in LP11 command neuron of defence behavior in snail Helix lucorum. Sensitizing stimulation during the intracellular injection of antisense olygonucleotide immediate early gene zif268 resulted in a selective suppression of synaptic facilitation in LP11 neuron responses evoked by tactile and chemical stimulation of the snail "head". At the same time, development of synaptic facilitation of responses in the LP11 neuron evoked by tactile stimulation of the foot was the same as in control sensitized snails. The results suggest that immediate early gene zif268 is selectively involved in the mechanisms of specific regulation of plasticity of the synaptic "input" of LP11 neuron from sensory receptors of the snail "head".