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Acute effects of cocaine on cochlear function.

B G Shivapuja·Z P Gu·S S Saunders·W S Quirk
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Abstract

The effects of a single administration of cocaine on the cochlea was evaluated by measuring amplitude-intensity functions of the N1 response of the auditory nerve. Amplitude-intensity functions of the N1 response to tone-pips of 500 Hz, 1, 2, 4 and 8 kHz were obtained before and after intraperitoneal injection of either saline, 3 mg/kg or 25 mg/kg of cocaine. N1 amplitudes were decreased after the administration of cocaine and this reduction was found to be dose dependent. The influence of cocaine on cochlear blood flow (CBF) was examined in order to test the possibility that cocaine induced reductions in CBF underlie these electro-physiological changes. Corresponding decreases in cochlear blood flow after cocaine exposure were observed.

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Acoustic StimulationAnimalsAuditory ThresholdChinchillaCocaineCochleaDose-Response Relationship, DrugElectrophysiologyInjections, IntraperitonealLaser-Doppler FlowmetryRandom AllocationRegional Blood FlowVestibulocochlear NerveJournal ArticleResearch Support, Non-U.S. Gov't

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B G Shivapuja, Z P Gu, S S Saunders, W S Quirk. 1993. Acute effects of cocaine on cochlear function.. https://doi.org/10.1016/0378-5955(93)90114-g

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