Reduced GABA(A) receptor-mediated tonic inhibition in aged rat auditory thalamus.

摘要: Age-related deficits in detecting and understanding speech, which can lead to social withdrawal isolation, have been linked changes the central auditory system. Many of these age-related involve altered mechanisms inhibitory neurotransmission, essential for accurate reliable processing. In sensory thalamus, GABA mediates fast (phasic) inhibition via synaptic GABA(A) receptors (GABA(A)Rs) long-lasting (tonic) high-affinity (extrasynaptic) GABA(A)Rs, provide a majority overall tone thalamus. Due delicate balance between excitation inhibition, alteration normal thalamic function with age reduction tonic GABA(A)R-mediated may disrupt adult processing, gating, thalamocortical rhythmicity, slow-wave sleep. The present study examines homeostatic plasticity GABA(A)R thalamus or medial geniculate body (MGB). Using slices from young (3-8 months) aged (28-32 rats, studies found 45.5% density 50.4% whole cell Cl(-) currents MGB. Synaptic appeared differentially affected lemniscal nonlemniscal Except resting membrane potential, basic properties were unaltered age, including neuronal homeostasis determined using gramicidin perforated patch-clamp method. Results demonstrate selective significant age-dependent within These data suggest that subtype agonists modulators might be used augment MGB improving speech understanding, sleep subset elderly individuals.