TY - CHAP M1 - Book, Section TI - NMDA Receptor Antagonism in Pain Therapy A1 - DeBonet, Alexander F. A2 - Bajwa, Zahid H. A2 - Wootton, R. Joshua A2 - Warfield, Carol A. PY - 2016 T2 - Principles and Practice of Pain Medicine, 3e AB - The synapse between the primary afferent and secondary afferent neurons in the dorsal horn of the spinal cord is a critical site for the modulation of ascending pain pathways. Glutamate is the primary excitatory amino acid (EAA) involved in excitation of the secondary afferent neuron and is primarily stored in the presynaptic vesicles of the primary afferent neuron. Upon membrane depolarization, glutamate is released and targets postsynaptic receptors, which can be either metabotropic or ionotropic. Ionotropic glutamate receptors are ligand-gated channels that regulate ion conductance of calcium and sodium. There are three major subclasses of ionotropic receptors: a-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), kainate, and N-methyl-D-aspartate (NMDA). The discovery of several pharmacologic agents, beginning with compound (+) MK-801, that are highly selective antagonists for specific subtypes of glutamate receptors has helped clarify the characteristics and functions of the various glutamate receptors and in particular the role of the NMDA calcium channel in the central nervous system (CNS).1 SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/11/13 UR - accessanesthesiology.mhmedical.com/content.aspx?aid=1131937376 ER -