Individual synaptic vesicles mediate stimulated exocytosis from cochlear inner hair cells.

ABSTRACT: Spontaneous excitatory postsynaptic currents (sEPSCs) measured from the first synapse in the mammalian auditory pathway reach a large mean amplitude with a high level of variance (CV between 0.3 and 1). This has led some to propose that each inner hair cell (IHC) ribbon-type active zone (AZ), on average, releases ∼6 synaptic vesicles (SVs) per sEPSC in a coordinated manner. If true, then the predicted change in membrane capacitance (C_m) for such multivesicular fusion events would equate to ∼300 attofarads (aF). Here, we performed cell-attached C_m measurements to directly examine the size of fusion events at the basolateral membrane of IHCs where the AZs are located. The frequency of events depended on the membrane potential and the expression of Ca_v1.3, the

SUBMITTER: Grabner CP 

PROVIDER: S-EPMC6294930 | biostudies-literature | 2018 Dec

REPOSITORIES: biostudies-literature