Dendritic HCN channels shape excitatory postsynaptic potentials at the inner hair cell afferent synapse in the mammalian cochlea.

ABSTRACT: Synaptic transmission at the inner hair cell (IHC) afferent synapse, the first synapse in the auditory pathway, is specialized for rapid and reliable signaling. Here we investigated the properties of a hyperpolarization-activated current (I(h)), expressed in the afferent dendrite of auditory nerve fibers, and its role in shaping postsynaptic activity. We used whole cell patch-clamp recordings from afferent dendrites directly where they contact the IHC in excised postnatal rat cochlear turns. Excitatory postsynaptic potentials (EPSPs) of variable amplitude (1-35 mV) were found with 10-90% rise times of about 1 ms and time constants of decay of about 5 ms at room temperature. Current-voltage relations recorded in afferent dendrites revealed I(h). The pharmacological profile and reversal pote

SUBMITTER: Yi E 

PROVIDER: S-EPMC2867566 | biostudies-literature | 2010 May

REPOSITORIES: biostudies-literature