O transportador XCG- medeia a captação de glutamato independente de sódio em cultura primária de células gliais da cóclea de camundongos neonatos

Abstract

The cochlea is a sensory organ of the auditory system whose excitatory synapses are mediated by L-Glutamate. Since glutamate has physiological and pathological repercussions on the cochlea, the crucial role of glutamate transport mechanisms capable of regulating the extracellular concentration of this neurotransmitter in order to maintain auditory function is highlighted. Within this context, in this study we sought to investigate the activity and expression of glutamate transport systems in an in vitro model of primary cultures of cochlear glial cells obtained from newborn mice of the Balb/C lineage. For this, we determined the sodium dependent and independent glutamate transport by means of glutamate uptake and release assays whose extracellular concentrations were quantified using High Performance Liquid Chromatography coupled to a fluorescence detector. Finally, the cells were subjected to immunofluorescence assay for XCG sodium-independent glutamate transporter labeling. In our results, we demonstrate that cochlear glial cells have a glutamate transport system mediated by the XCG- transporter. Such data suggest a possible role of this transporter in the control of extracellular concentrations of glutamate and regulation of the redox state, which may help to preserve auditory function.