[Transcription factors C/EBP inhibition specifically affects synaptic plasticity in the snail's neuron]

In our previous investigations it was found that nociceptive sensitization is followed by a long-term facilitation of synaptic transmission in command neuron of defence behavior. The facilitation is translation- and transcription-dependent. Features of plasticity neurochemical mechanisms of different sensory inputs in the neural cells were determined. NMDA glutamate receptors, serotonin receptors, cAMP as well as serotonin-modulated protein SMP-69 are involved in mechanisms of induction of neural response facilitation in LPl 1 neuron evoked by chemical sensory stimulation of snail head. Protein kinase C is involved in synaptic facilitation-induction mechanisms from other sensory neural input--tactile receptors of snail "head". In this work, participation of C/EBP (CCAAT-enhancing-binding protein) immediate early gene transcription factor was established in mechanisms of synapse-specific plasticity during sensitization in LPl 1 neuron in snail Helix lucorum. Specific binding with C/EBP oligonucleotides were used as C/EBP inhibitors. It was found that sensitization during intracellular oligonucleotide injection selectively suppressed synaptic facilitation in LPl 1 neuron responses evoked by chemical sensory stimulation of snail "head". At the same time, development of synaptic facilitation of the neuron responses evoked by tactile stimulation of snail head or foot was the same as in control sensitized snails. It seems that C/EBP transcription factor is selectively involved in mechanisms of synapse-specific plasticity of sensory input in LPl 1 neuron from snail head chemoreceptors.