Impulse-dependent and tetrodotoxin-sensitive release of GABA in the rat's substantia nigra measured by microdialysis.
Brain Res
; 684(2): 172-8, 1995 Jul 03.
Article
em En
| MEDLINE
| ID: mdl-7583219
ABSTRACT
gamma-Aminobutyric acid (GABA) release in the rat substantia nigra pars reticulata (SNR) was studied by microdialysis coupled with high-performance liquid chromatography and fluorimetric detection. Electrical stimulation of striatonigral axons in the internal capsule (IC) increased nigral GABA release in conscious and halothane-anaesthetized rats. This was prevented by intranigral infusion of tetrodotoxin (TTX) while basal GABA release was unaffected. Calcium-free, cobalt-containing (2 mM CoCl2) artificial cerebrospinal fluid reduced basal GABA overflow but not that evoked with high K+ (100 mM). Extracellular levels of glutamate (GLU) and taurine (TAU) were not modified by IC stimulation, TTX or 0 Ca2+ although high K+ promoted GABA and TAU release but not that of GLU. These data demonstrate an impulse-and sodium-dependent release of GABA from nigral afferent neurones which contribute little to the extracellular concentration of GABA under steady-state conditions.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Tetrodotoxina
/
Substância Negra
/
Ácido gama-Aminobutírico
Tipo de estudo:
Diagnostic_studies
Limite:
Animals
Idioma:
En
Revista:
Brain Res
Ano de publicação:
1995
Tipo de documento:
Article
País de afiliação:
Reino Unido