Role of excitatory amino acid receptors in cardiorespiratory coupling in ventrolateral medulla

271 (Regulatory Integrative Comp. Physiol. 40): R1221-R12-10, 1996.-The role of (t)-cll-amino-3-hydroxy-/j-methyl-isoxazole-4-propionic acid (AMPA)-kainate and N-methyl-n-aspartatc (NMDA) receptors in the rostra1 ventrolateral medulla (RVLM) and caudal ventrolateral medulla (CVLM) on the central respiratory drive (CRD)-related activity of splanchnic sympathetic nerve activity (SNA) was examined in rats. SNA increased during inspiration (I peak) and postinspiration (PI peak). Bilateral microinjections of 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX; AMPA-kainate antago-nist) or r,l,-2-amino-5phosphonovaleric acid (APV, NMDA antagonist) into RVLM abolished the PI, but not the I, peak. Blockade of all excitatory amino acid receptors in RVLM with kynurenate, or mixtures of APV and CNQX, also failed to eliminate the I peak. Somatosympathetic responses wer