Inhibition of gamma-aminobutyric acid receptor-gated chloride currents by noradrenaline in rat spiral ganglion neuron / 中华耳鼻咽喉头颈外科杂志
Chinese Journal of Otorhinolaryngology Head and Neck Surgery
; (12): 302-305, 2008.
Article
em Zh
| WPRIM
| ID: wpr-248180
Biblioteca responsável:
WPRO
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the pharmacological modulatory properties of noradrenaline in the rat spiral ganglion neuron.</p><p><b>METHODS</b>Nystatin perforated patch recording technique under voltage-clamp conditions was used to record the modulatory effect of noradrenaline on the current evoked by gamma-amino butyric acid (GABA) in the spiral ganglion neuron.</p><p><b>RESULTS</b>The reversal potential of the GABA response was about (- 0.78 +/- 0.05) mV (n = 8), which was almost identical to the theoretical Cl- equilibrium potential. At the holding potential of -50 mV, GABA evoked inward current (I(GABA)) over the concentration range of 0.3 to 1 micromol/L. The EC50 and Hill coefficient for GABA were (5.2 +/- 0.5) micromol/L and 1.03 (n = 26). The I(GABA) was suppressed by bicuculline, the selective GABA-A receptor antagonist, and the chloride currents evoked by GABA was inhibited by noradrenaline.</p><p><b>CONCLUSIONS</b>The result indicates that noradrenaline depressed GABA-A receptor-gated chloride currents, which may contribute to the modulatory effect of sympathetic system on auditory transmission.</p>
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Índice:
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Assunto principal:
Farmacologia
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Norepinefrina
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Gânglio Espiral da Cóclea
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Ratos Sprague-Dawley
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Receptores de GABA
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Canais de Cloreto
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Técnicas de Patch-Clamp
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Antagonistas de Receptores de GABA-A
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Metabolismo
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Neurônios
Limite:
Animals
Idioma:
Zh
Revista:
Chinese Journal of Otorhinolaryngology Head and Neck Surgery
Ano de publicação:
2008
Tipo de documento:
Article