KCNJ10 (Kir4.1) potassium channel knockout abolishes endocochlear potential.
Stria vascularis of the cochlea generates the endocochlear potential and secretes K(+). K(+) is the main charge carrier and the endocochlear potential the main driving force for the sensory transduction that leads to hearing. Stria vascularis consists of two barriers, marginal cells that secrete potassium and basal cells that are coupled via gap junctions to intermediate cells. Mice lacking the KCNJ10 (Kir4.1) K(+) channel in strial intermediate cells did not generate an endocochlear potential. Endolymph volume and K(+) concentration ([K(+)]) were reduced. These studies establish that the KCNJ10 K(+) channel provides the molecular mechanism for generation of the endocochlear potential in concert with other transport pathways that establish the [K(+)] difference across the channel. KCNJ10 is also a limiting pathway for K(+) secretion.
Marcus
Daniel C
DC
Department of Anatomy and Physiology, Kansas State University, Manhattan, Kansas 66506-5802, USA. marcus@ksu.edu
Wu
Tao
T
Wangemann
Philine
P
Kofuji
Paulo
P
D000818:Animals; D003051:Cochlea / Q000473:pathology; D003055:Cochlear Microphonic Potentials / Q000502:physiology*; D004710:Endolymph / Q000378:metabolism; D051379:Mice; D018345:Mice, Knockout / Q000235:genetics; D011188:Potassium / Q000378:metabolism; D015221:Potassium Channels / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D024661:Potassium Channels, Inwardly Rectifying; D012016:Reference Values; D013316:Stria Vascularis / Q000166:cytology / Q000378:metabolism / Q000502:physiology
D015221:Potassium Channels; D024661:Potassium Channels, Inwardly Rectifying; D011188:Potassium