Glycine receptor-mediated inhibition of dopamine and non-dopamine neurons of the rat ventral tegmental area in vitro.
Dopaminergic and non-dopaminergic neurons of the ventral tegmental area (VTA) were recorded intracellularly in slices of rat midbrain. Glycine (0.1-3 mM) caused a strychnine-sensitive and chloride-dependent reduction in membrane input resistance in both types of neuron. However, glycine also reduced the frequency of spontaneous bicuculline-sensitive inhibitory postsynaptic potentials (IPSPs) when recorded in dopaminergic cells. We conclude that glycine inhibits both types of VTA neuron by activating a strychnine-sensitive chloride conductance. Our data also raise the possibility that glycine could increase dopamine output from the VTA by a mechanism of disinhibition.
Zheng
F
F
Department of Physiology and Pharmacology, L-334, Oregon Health Sciences University, 3181 SW Sam Jackson Park Road, Portland, OR 97201, USA.
Johnson
S W
SW
D000200:Action Potentials / Q000187:drug effects / Q000502:physiology; D000818:Animals; D004298:Dopamine / Q000378:metabolism*; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D018756:GABA Antagonists / Q000494:pharmacology; D005998:Glycine / Q000378:metabolism* / Q000494:pharmacology; D018684:Glycine Agents / Q000494:pharmacology; D007736:Kynurenic Acid / Q000031:analogs & derivatives* / Q000494:pharmacology; D008297:Male; D009433:Neural Inhibition / Q000187:drug effects / Q000502:physiology*; D009474:Neurons / Q000187:drug effects / Q000378:metabolism*; D009924:Organ Culture Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D018009:Receptors, Glycine / Q000187:drug effects / Q000378:metabolism*; D013331:Strychnine / Q000494:pharmacology; D009435:Synaptic Transmission / Q000187:drug effects / Q000502:physiology*; D013779:Tetrodotoxin / Q000494:pharmacology; D017557:Ventral Tegmental Area / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
D018691:Excitatory Amino Acid Antagonists; D018756:GABA Antagonists; D018684:Glycine Agents; D018009:Receptors, Glycine; D013779:Tetrodotoxin; D005680:gamma-Aminobutyric Acid; D007736:Kynurenic Acid; D013331:Strychnine; C057013:7-chlorokynurenic acid; D005998:Glycine; D004298:Dopamine