The Effects of NMDA Receptor Blockade on Sensory-Evoked Responses in Superficial Layers of the Rat Barrel Cortex

• Published in: Frontiers in cellular neuroscience Vol. 13; p. 259
• Main Authors: Lebedeva, Julia, Zakharov, Andrey, Burkhanova, Gulshat, Chernova, Kseniya, Khazipov, Roustem
• Format: Journal Article
• Language: English
• Published: Switzerland Frontiers Research Foundation 07.06.2019; Frontiers; Frontiers Media S.A
• Subjects: APV; barrel cortex; Cement; Cortex (barrel); epipial application; Glutamic acid receptors (ionotropic); Laboratory animals; Life Sciences; N-Methyl-D-aspartic acid receptors; Neurobiology; Neurons; Neurons and Cognition; Neuroscience; Neurosciences; NMDA receptor; Sensory integration; Sensory neurons; sensory-evoked potential; Signal processing; Somatosensory cortex; Surgery; Unit activity; α-Amino-3-hydroxy-5-methyl-4-isoxazole propionic acid; United States > US; Russia; barrel cortex; sensory-evoked potential; epipial application; NMDA receptor; APV
• ISSN: 1662-5102; 1662-5102
• DOI: 10.3389/fncel.2019.00259

Transmission of excitation from L4 to L2/3 is a part of a canonical circuit of cortical sensory signal processing. While synapses from L4 to L2/3 are mediated by both AMPA and NMDA glutamate receptors, previous studies suggested that sensory-evoked excitation of neurons in supragranular layers is almost entirely mediated by NMDA receptors. Here, we readdressed this question using extracellular recordings of sensory-evoked potentials (SEPs) and multiple unit activity (MUA) in the rat barrel cortex. We found that blockade of NMDA receptors using the selective antagonist dAPV profoundly inhibited the late part of L2/3 SEP, the associated sink, and MUA response but did not affect its initial part. Our results indicate that both non-NMDA and NMDA receptors are involved in sensory signal transmission from L4 to L2/3. While non-NMDA receptors mediate fast transmission of sensory signals, NMDA-Rs are importantly involved in the generation of the late phase of the sensory-evoked response in supragranular layers.