Excess extracellular K⁺ causes inner hair cell ribbon synapse degeneration.

ABSTRACT: Inner hair cell (IHC) ribbon synapses are the first synapse in the auditory system and can be degenerated by noise and aging, thereby leading to hidden hearing loss (HHL) and other hearing disorders. However, the mechanism underlying this cochlear synaptopathy remains unclear. Here, we report that elevation of extracellular K⁺, which is a consequence of noise exposure, could cause IHC ribbon synapse degeneration and swelling. Like intensity dependence in noise-induced cochlear synaptopathy, the K⁺-induced degeneration was dose-dependent, and could be attenuated by BK channel blockers. However, application of glutamate receptor (GluR) agonists caused ribbon swelling but not degeneration. In addition, consistent with synaptopathy in HHL, both K⁺ and noise exp

SUBMITTER: Zhao HB 

PROVIDER: S-EPMC7782724 | biostudies-literature | 2021 Jan

REPOSITORIES: biostudies-literature