RESUMO
Changes in conditioned reflex spike activity of neurons in the sensorimotor cortex were studied during microiontophoretic application of agonists and antagonists of glutamate and GABAergic transmission. The results of these experiments showed that the glutamate ionotropic receptors (AMPA and NMDA) of neurons in the sensorimotor cortex were intensely activated by the arrival of a conditioned signal in the cortex. This response included not only large pyramidal neurons of the deep cortical layers, but also the surrounding inhibitory interneurons. The existence of constant tonic inhibitory regulation of the activity of large pyramidal neurons by the surrounding inhibitory cells was demonstrated, along with the active involvement of this inhibition in organizing the excitatory responses of neurons in the sensorimotor cortex during a conditioned reflex.
Assuntos
Condicionamento Clássico/fisiologia , Ácido Glutâmico/fisiologia , Córtex Motor/fisiologia , Neurônios/fisiologia , Córtex Somatossensorial/fisiologia , Transmissão Sináptica , Potenciais de Ação , Animais , Gatos , Agonistas de Aminoácidos Excitatórios/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , Agonistas GABAérgicos/farmacologia , Antagonistas GABAérgicos/farmacologia , Iontoforese , Córtex Motor/citologia , Córtex Motor/efeitos dos fármacos , Neurônios/efeitos dos fármacos , Células Piramidais/efeitos dos fármacos , Células Piramidais/fisiologia , Córtex Somatossensorial/citologia , Córtex Somatossensorial/efeitos dos fármacos , Transmissão Sináptica/efeitos dos fármacosRESUMO
Changes in conditioned impulse reactions of neurons in sensorimotor cortex were studied during microiontophoretic application of glutamatergic and GABA ergic agonistic and antagonistic drugs. It was shown that ionotropic glutamate receptors (AMPA and NMDA) are activated by a conditioned stimulus. Not only large pyramidal neurons of deep cortical layers but surrounding short-axon inhibitory interneurons are involved in the reaction. It was shown that the activity of pyramidal neurons is under a constant inhibitory control from surrounding interneurons. This inhibition is involved in organization of excitatory cortical responses during conditioning.