AJP - Renal Physiology, Vol 253, Issue 1 59-F65, Copyright © 1987 by American Physiological Society
Facilitated transfer of glucose from blood into perilymph in the rat cochlea
E. Ferrary, O. Sterkers, G. Saumon, P. Tran Ba Huy and C. Amiel
The transport of glucose into cochlear endolymph, perilymph of scala
vestibuli and perilymph of scala tympani, and cerebrospinal fluid (CSF) was
studied after intravenous administration of tracers of D-glucose,
L-glucose, and 3-O-methyl-D-glucose in anesthetized rats. The data showed
that D-glucose concentrations in perilymph of scala vestibuli, perilymph of
scala tympani, and CSF were approximately 50%, and in endolymph less than
10%, that in plasma; D-glucose concentration in perilymph of scala
vestibuli, perilymph of scala tympani, and CSF increased as a linear
function of that in plasma; D-glucose entry into perilymph of scala
vestibuli, perilymph of scala tympani, and CSF was more rapid than that of
L-glucose; after infusion of 3-O-methyl-D-glucose, but not after that of
mannitol, both the D-glucose concentration ratio of perilymph over plasma
and D-glucose transfer into perilymph were lowered. These results indicate
that D-glucose enters into perilymph of scala vestibuli by a facilitated
transport, possibly located at the blood-perilymph barrier.
