A physiological role for dopamine as modulator of GABA effects in substantia nigra: supersensitivity in 6-hydroxydopamine-lesioned rats.
Dopamine has been reported to attenuate the inhibitory effects of gamma-aminobutyric acid (GABA) on substantia nigra pars reticulata neurons. Five to six weeks after rats received 6-hydroxydopamine lesions of the nigral dopamine neurons, the ability of iontophoretically applied dopamine to attenuate pars reticulata responses to GABA was increased by 40% (P less than 0.05) with respect to that of unlesioned rats. These results suggest that the dopamine sites which mediate this modulatory interaction may become supersensitive in animals with dopamine-deficient nigras.
D000818:Animals; D004298:Dopamine / Q000502:physiology*; D006892:Hydroxydopamines; D008297:Male; D016627:Oxidopamine; D051381:Rats; D011919:Rats, Inbred Strains; D011954:Receptors, Dopamine / Q000502:physiology*; D013378:Substantia Nigra / Q000187:drug effects*; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
D006892:Hydroxydopamines; D011954:Receptors, Dopamine; D005680:gamma-Aminobutyric Acid; D016627:Oxidopamine; D004298:Dopamine