© 1992 Oxford University Press
research-article |
Effects of Aminoglycoside Antibiotics on the Auditory Brainstem Response and Post Rotatory Nystagmus in Rats
Research and Development Division, Takeda Chemical Industries, Ltd. 6-10-1 Himuro-cho, Takatsuki, Osaka 569, Japan
Received January 2, 1991; accepted November 1, 1991
Effects of three aminoglycoside antibiotics, amikacin (AMIK), tobramycin (TOB), and gentamicin (GM), on the auditory and vestibular functions were assessed in rats, the most frequently used species in toxicity studies. Chronic electrodes for auditory brainstem response (ABR) recording were implanted on the epidural surface, and those for post rotatory nystagmus (PRN) were implanted at the nictitating membrane and the outer canthus. AMK, TOB, and GM were given intramuscularly twice daily for 34 weeks at a daily dose of 350, 150, and 100 mg/kg, respectively. The amplitude of each wave of the ABR was decreased or disappeared in the groups treated with AMK, TOB, and GM. In the PRN, the duration of the nystagmus was decreased in the TOB group and completely lost in the GM group. No abnormality was observed in the PRN in the AMK group. These results were similar to those reported in the ototoxicity studies of these drugs in guinea pigs and indicate that ototoxicity can be evaluated in rats as successfully as in guinea pigs by this procedure.