Is the endolymphatic K secretion electrogenic?
The endolymphatic potential is assumed to result from active K transport into the endolymphatic compartment and passive K diffusion in the opposite direction. However, in several in vivo experiments, changes in the endolymphatic potential differed from those in the endolymphatic K concentration. Moreover, in in vitro experiments, a negative endolymphatic potential was observed in the presence of ouabain without K gradient between the two compartments. These observations suggest that the coupling between the K transport and the genesis of the endolymphatic potential is not tight. Several factors may separately influence the endolymphatic potential and the K transport such as the acid-base equilibrium, the integrity of Reissner's membrane, the hormonal status, and the Na transport.
INSERM U.251, Faculté Xavier Bichat, Université Paris, France.
E
E
Ferrary
C
C
Bernard
N
N
Julien
O
O
Sterkers
C
C
Amiel
D000818:Animals; D003055:Cochlear Microphonic Potentials / Q000502:physiology; D004710:Endolymph / Q000378:metabolism*; D017136:Ion Transport; D011188:Potassium / Q000378:metabolism*; D011893:Rana esculenta; D012665:Semicircular Canals / Q000502:physiology
D011188:Potassium