The effects of three concentrations of neomy-cin, administered by a method of acute perilymphatic per-fusion of the guinea pig cochlea, on the cochlear micro-phonic potential (CM) at 4 kHz and 500 Hz are described. A concentration-dependent reduction in CM occurred during the 60 minute perfusion period. Neomycin at 10-4 M did not change the CM magnitude, while at 10-3 and 10-2 M it caused 4 kHz (and 500 Hz) CM reductions which began within 24 (for both frequencies) minutes and 10 (and 12) minutes of drug application respectively. CM reduction proceeded at a higher rate for greater neomycin concentration. The perfusion technique, the implication of the frequency indifference, and the potential of the perfusion technique for inner ear biochemical analysis are discussed.
ASJC Scopus subject areas