Cobalt-permeable non-NMDA receptors in developing chick brainstem auditory nuclei.
Kainate, an agonist at non-NMDA glutamate receptors, evoked strong concentration-dependent cobalt accumulation in the chick brain stem auditory nuclei angularis, laminaris (NL) and magnocellularis (NM). This effect could be blocked completely by the AMPA/kainate receptor antagonist CNQX and the AMPA antagonist GYKI 53655 but not by antagonists of NMDA receptors or voltage-sensitive calcium channels. Kainate (30 microM) evoked cobalt uptake from embryonic day (E)9 through E21, with a peak intensity at E15. Before E13, uptake occurred mainly in NL but declined markedly in NM after E15 and ceased in NL by E21. We conclude that calcium-permeable non-NMDA receptors are transiently expressed at the time when mature neuronal number, form and synaptic connectivity are established.
Zhou
N
N
Department of Neurobiology and Anatomy, University of Utah School of Medicine, Salt Lake City 84132, USA.
Taylor
D A
DA
Parks
T N
TN
D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000161:Acoustic Stimulation; D000818:Animals; D001306:Auditory Pathways / Q000196:embryology / Q000378:metabolism*; D001569:Benzodiazepines / Q000494:pharmacology; D001933:Brain Stem / Q000187:drug effects / Q000196:embryology / Q000378:metabolism*; D002463:Cell Membrane Permeability; D002642:Chick Embryo; D003035:Cobalt / Q000378:metabolism*; D016057:Evoked Potentials, Auditory, Brain Stem / Q000502:physiology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D007608:Kainic Acid / Q000037:antagonists & inhibitors / Q000494:pharmacology; D009474:Neurons / Q000378:metabolism*; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000378:metabolism*; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000037:antagonists & inhibitors / Q000494:pharmacology
D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; D001569:Benzodiazepines; C079692:GYKI 53655; D003035:Cobalt; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D007608:Kainic Acid