Intravenous GABA agonist administration stimulates firing of A10 dopaminergic neurons.
Increasing intravenous doses of two gamma-aminobutyric acid (GABA) agonists, muscimol and 4,5,6,7-tetrahydroisoxazolo-[5,4-c]-pyridin-3-ol (THIP), caused dose-related increases in extracellular, single unit activity of A10 dopaminergic neurons of the ventral tegmental area. Muscimol, the more potent of the two compounds, stimulated firing at doses approximately 15-20 times lower than the doses of THIP required to elicit equivalent excitatory effects. The maximum stimulation achieved was approximately 150 and 140% of the baseline firing rate for muscimol and THIP, respectively.
D000818:Animals; D004298:Dopamine / Q000502:physiology*; D007275:Injections, Intravenous; D007555:Isoxazoles / Q000008:administration & dosage / Q000494:pharmacology; D008032:Limbic System / Q000187:drug effects*; D009118:Muscimol / Q000008:administration & dosage / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects*; D051381:Rats; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
D007555:Isoxazoles; D009118:Muscimol; D005680:gamma-Aminobutyric Acid; C015542:gaboxadol; D004298:Dopamine