[Acetylsalicylic acid does not alter the mechanoelectrical transduction of mammalian outer hair cells in vitro]. / Die mechanoelektrische Transduktion der äusseren Haarzelle wird durch Azetylsalizylsäure in vitro nicht beeinflusst.

ABSTRACT

BACKGROUND: High doses of acetylsalicylic acid (ASS) induce tinnitus and hearing loss. This ototoxic side effect of ASS is characterized by a decrease in spontaneous and evoked otoacoustic emissions. A decrease in otoacoustic emissions is found not only in mammals, but also in non-mammalian ears without electromotile outer hair cells. The molecular mechanism underlying ASS ototoxicity seems to be competitive binding to and a block of the motor molecule prestin. In non-mammalian species, ASS ototoxicity is possibly explained by an effect on the hair bundle. RESULTS: The present data from the outer hair cells of the adult guinea pig cochlea show a reduction in the membrane capacitance by maximally 42%, probably as a result of ASS binding competitively to the motor molecule. However, spontaneous and evoked receptor currents were not modulated by ASS. CONCLUSION: The results suggest an influence of ASS on outer hair cell somatic electromotility, without a concomitant effect on hair-bundle function.