Inhibitory effect of erythromycin on ion transport by stria vascularis and vestibular dark cells.
A previous study showed that systemic administration of erythromycin caused a reversible decline in the endocochlear and cochlear microphonic potentials. Those data were thought to suggest that erythromycin caused hearing loss by interference with ion transport processes in the stria vascularis. The present study was undertaken to test this hypothesis by measuring the effects of erythromycin perfused on either the apical or basolateral side on the transepithelial short circuit current (Isc), a measure of the K+ secretion rate. Isc was measured from preparations of strial marginal cells and the homologous vestibular dark cells in vitro with a micro-Ussing chamber. Erythromycin was found to have no effect when perfused on the apical side but to cause a reversible decrease in Isc when perfused on the basolateral side for both epithelia. These data are consistent with the notion that at least one ototoxic effect of erythromycin is the inhibition of K+ secretion in the inner ear.
Liu
J
J
Biophysics Laboratory, Boys Town National Research Hospital, Omaha, NE 68131, USA.
Marcus
D C
DC
Kobayashi
T
T
D000818:Animals; D002478:Cells, Cultured; D003051:Cochlea / Q000187:drug effects / Q000378:metabolism; D003055:Cochlear Microphonic Potentials / Q000187:drug effects; D015194:Diffusion Chambers, Culture; D017097:Electric Impedance; D004594:Electrophysiology; D004847:Epithelial Cells; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D004917:Erythromycin / Q000008:administration & dosage / Q000494:pharmacology*; D005849:Gerbillinae; D017136:Ion Transport / Q000187:drug effects; D011188:Potassium / Q000378:metabolism; D026902:Potassium Channel Blockers; D015221:Potassium Channels / Q000187:drug effects; D012665:Semicircular Canals / Q000166:cytology / Q000187:drug effects / Q000378:metabolism; D013316:Stria Vascularis / Q000187:drug effects* / Q000378:metabolism; D014722:Vestibule, Labyrinth / Q000166:cytology / Q000187:drug effects* / Q000378:metabolism
D026902:Potassium Channel Blockers; D015221:Potassium Channels; D004917:Erythromycin; D011188:Potassium