Effects of noise-induced hearing loss on parvalbumin and perineuronal net expression in the mouse primary auditory cortex.

Effects of noise-induced hearing loss on parvalbumin and perineuronal net expression in the mouse primary auditory cortex.
Hear Res. 2017 Apr 27;350:82-90
Authors: Nguyen A, Khaleel HM, Razak KA
Abstract
Noise induced hearing loss is associated with increased excitability in the central auditory system but the cellular correlates of such changes remain to be characterized. Here we tested the hypothesis that noise-induced hearing loss causes deterioration of perineuronal nets (PNNs) in the auditory cortex of mice. PNNs are specialized extracellular matrix components that commonly enwrap cortical parvalbumin (PV) containing GABAergic interneurons. Compared to somatosensory and visual cortex, relatively less is known about PV/PNN expression patterns in the primary auditory cortex (A1). Whether changes to cortical PNNs follow acoustic trauma remains unclear. The first aim of this study was to characterize PV/PNN expression in A1 of adult mice. PNNs increase excitability of PV+ inhibitory neurons and confer protection to these neurons against oxidative stress. Decreased PV/PNN expression may therefore lead to a reduction in cortical inhibition. The second aim of this study was to examine PV/PNN expression in superficial (I-IV) and deep cortical layers (V-VI) following noise trauma. Exposing mice to loud noise caused an increase in hearing threshold that lasted at least 30 days. PV and PNN expression in A1 was analyzed at 1, 10 and 30 day...

Source: Hearing Research - April 27, 2017 Category: Audiology Authors: Nguyen A, Khaleel HM, Razak KA Tags: Hear Res Source Type: research