Developmental alterations in NMDA receptor-mediated currents in neonatal rat spinal motoneurons.
Postnatal development of N-methyl-D-aspartate (NMDA) receptors expressed in motoneurons was studied by tight-seal whole-cell recordings from identified motoneurons in slices of neonatal rat spinal cord. The magnitude of NMDA-induced currents was large during the early postnatal period, and then it decreased gradually through postnatal day (PND) 15. The pharmacological properties of NMDA-induced currents altered during this period, suggesting that the combination of NMDA receptor subunits changes during development. The magnitude of the NMDA receptor-mediated component of excitatory postsynaptic current evoked by electrical stimulation of an adjacent neuron also decreased from PNDs 1-5 through PNDs 11-15. NMDA receptors appear to underlie the mechanisms of activity-dependent development of spinal motoneurons during early postnatal life.
Department of Physiology, Kyorin University School of Medicine, Tokyo, Japan.
Y
Y
Hori
K
K
Kanda
D015763:2-Amino-5-phosphonovalerate / Q000494:pharmacology; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione / Q000494:pharmacology; D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D001640:Bicuculline / Q000494:pharmacology; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D005260:Female; D018756:GABA Antagonists / Q000494:pharmacology; D018684:Glycine Agents / Q000494:pharmacology; D009046:Motor Neurons / Q000187:drug effects / Q000502:physiology* / Q000648:ultrastructure; D016202:N-Methylaspartate / Q000494:pharmacology; D018408:Patch-Clamp Techniques; D049590:Postpartum Period / Q000502:physiology; D011247:Pregnancy; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000819:agonists / Q000037:antagonists & inhibitors / Q000502:physiology*; D013116:Spinal Cord / Q000166:cytology*; D013331:Strychnine / Q000494:pharmacology; D013779:Tetrodotoxin / Q000494:pharmacology; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology
D018690:Excitatory Amino Acid Agonists; D018691:Excitatory Amino Acid Antagonists; D018756:GABA Antagonists; D018684:Glycine Agents; D016194:Receptors, N-Methyl-D-Aspartate; D013779:Tetrodotoxin; D016202:N-Methylaspartate; D018750:6-Cyano-7-nitroquinoxaline-2,3-dione; D015763:2-Amino-5-phosphonovalerate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D013331:Strychnine; D001640:Bicuculline