title: Nitric oxide facilitates N-methyl-D-aspartate-induced burst firing in dopamine neurons from rat midbrain slices.
abstract: Dopamine (DA) neurons in the ventral tegmental area and substantia nigra pars compacta were induced to fire in bursts with application of N-methyl-D-aspartate (NMDA, 20 microM) and apamin (100 nM) while recording intracellularly in the rat brain slice. L-Arginine (300 microM), a substrate for nitric oxide (NO) production, increased both the number of spikes per burst and the magnitude of interburst hyperpolarizations. Nitric oxide synthase inhibitors N-nitro-L-arginine methyl ester (L-NAME, 100 microM), N-nitro-L-arginine, and 7-nitroindazole inhibited NMDA-induced burst firing by reducing the number of spikes per burst. Moreover, L-arginine (100 microM) reversed the inhibition of burst firing produced by L-NAME. These findings suggest that NO facilitates NMDA-induced burst firing in DA neurons.
authors.affiliation: Department of Physiology and Pharmacology, Oregon Health Sciences University, Portland 97201, USA.
authors.forename: B A
authors.initials: BA
authors.lastname: Cox
authors.forename: S W
authors.initials: SW
authors.lastname: Johnson
mesh_terms: D000818:Animals; D001030:Apamin / Q000494:pharmacology; D001120:Arginine / Q000494:pharmacology; D004298:Dopamine / Q000378:metabolism*; D004357:Drug Synergism; D004594:Electrophysiology; D004791:Enzyme Inhibitors / Q000494:pharmacology; D066298:In Vitro Techniques; D007191:Indazoles / Q000494:pharmacology; D008297:Male; D008636:Mesencephalon / Q000166:cytology / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D016202:N-Methylaspartate / Q000494:pharmacology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D009569:Nitric Oxide / Q000502:physiology*; D019335:Nitroarginine / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D004791:Enzyme Inhibitors; D007191:Indazoles; D019335:Nitroarginine; D001030:Apamin; D009569:Nitric Oxide; D016202:N-Methylaspartate; D001120:Arginine; C080122:7-nitroindazole; D019331:NG-Nitroarginine Methyl Ester; D004298:Dopamine