Referenced in: none

Automatically associated channels: Kv7.2 , Kv7.3

Title: An M-like potassium current in the guinea pig cochlea.

Authors: Guihua Liang, Ernest J Moore, Mats Ulfendahl, Bo Rydqvist, Leif Jarlebark

Journal, date & volume: ORL J. Otorhinolaryngol. Relat. Spec., 2005 , 67, 75-82

PubMed link: http://www.ncbi.nlm.nih.gov/pubmed/15855814

Abstract
Potassium M currents play a role in stabilizing the resting membrane potential. These currents have previously been identified in several cell types, including sensory receptors. Given that maintaining membrane excitability is important for mechano-electrical transduction in the inner ear, the presence of M currents was investigated in outer hair cells isolated from the guinea pig hearing organ. Using a pulse protocol designed to emphasize M currents with the whole-cell patch-clamp technique, voltage- and time-dependent, non-inactivating, low-threshold currents (the hallmarks of M currents) were recorded. These currents were significantly reduced by cadmium chloride. Results from RT-PCR analysis indicated that genes encoding M channel subunits KCNQ2 and KCNQ3 are expressed in the guinea pig cochlea. Our data suggest that guinea pig outer hair cells express an M-like potassium current that, following sound stimulation, may play an important role in returning the membrane potential to resting level and thus regulating outer hair cell synaptic mechanisms.