Burst firing in dopamine neurons induced by N-methyl-D-aspartate: role of electrogenic sodium pump.
Dopamine-containing neurons of the mammalian midbrain are required for normal behavior and movements. In vivo they fire action potentials in bursts, but in vitro they discharge regularly spaced action potentials. Burst firing in vitro has now been shown to be robustly induced by the glutamate agonist N-methyl-D-aspartate (NMDA) although not by the non-NMDA agonists kainate or quisqualate. The hyperpolarization between bursts of action potentials results from electrogenic sodium ion extrusion by a ouabain-sensitive pump. This mechanism of burst generation in mammalian neurons may be important in the pathophysiology of schizophrenia and Parkinson's disease.
Johnson
S W
SW
Vollum Institute, Oregon Health Sciences University, Portland 97201.
Seutin
V
V
North
R A
RA
D000200:Action Potentials / Q000502:physiology; D000818:Animals; D002478:Cells, Cultured; D004298:Dopamine / Q000502:physiology*; D007608:Kainic Acid / Q000494:pharmacology; D016202:N-Methylaspartate / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects* / Q000502:physiology; D016318:Quisqualic Acid / Q000494:pharmacology; D051381:Rats; D012964:Sodium / Q000502:physiology; D000254:Sodium-Potassium-Exchanging ATPase / Q000502:physiology*; D009435:Synaptic Transmission / Q000502:physiology*
D016202:N-Methylaspartate; D016318:Quisqualic Acid; D012964:Sodium; D000254:Sodium-Potassium-Exchanging ATPase; D007608:Kainic Acid; D004298:Dopamine