[The selective effect of NMDA glutamate receptor antagonist on plasticity of sensory inputs from chemoreceptors of snail head during nociceptive sensitization].
The effects of N-methyl-D-aspartate (NMDA) glutamate receptor antagonist (+)-MK-801 hydrogen maleate (MR801) on plasticity of different sensory inputs of the L-RPl1 command neurons were studied in Helix lucorum snail during nociceptive sensitization. Application of sensitizing stimulation onto the snail head or foot in the control semi-intact preparation initiated depression of neural responses evoked by tactile or chemical sensory stimulation during the short-term period of sensitization and significant facilitation of neural responses during the long-period of sensitization. Sensitizing stimulation of snail head against the background of MK-801 application (10-30 microM) produced a pronounced depression of neural responses to chemical stimulation of the head both in the short- and long-term sensitization periods. At the same time, sensitizing stimulation of the foot or head during the MK-801 application produced the same changes in neural responses to chemical stimulation of the foot and tactile stimulation of the foot or head as in the control preparation. It can be suggested that NMDA-like glutamate receptors are selectively involved in the mechanisms of plasticity induction in the synaptic inputs of the command LPl1 and RPl1 neurons, which process the information resulting from chemical excitation of the snail head (a specific receptor skin site for these neurons in Helix lucorum).
Nikitin
V P
VP
Anokhin Institute of Normal Physiology, Russian Academy of Medical Sciences, Moscow.
Kozyrev
S A
SA
Shevelkin
A V
AV
D000818:Animals; D002628:Chemoreceptor Cells / Q000187:drug effects / Q000502:physiology*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D006372:Helix, Snails / Q000502:physiology*; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D018696:Neuroprotective Agents / Q000494:pharmacology; D009619:Nociceptors / Q000502:physiology; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors / Q000502:physiology*
D018696:Neuroprotective Agents; D016194:Receptors, N-Methyl-D-Aspartate; D016291:Dizocilpine Maleate