Abstract
Kanamycin (KM)-induced auditory disturbance in dogs was followed by time lapse recording of auditory brainstem response (ABR) and blood chemical examination. KM was administered subcutaneously to 6 beagle dogs 4 to 7-months of age at daily doses of 125, 250, and 500mg/kg for 13 to 71 times. At the end of the experiments the dogs were sacrificed and their kidneys and inner ears were examined histologically. KM-induced auditory disturbance at about 6, 500mg/kg of total dose in beagle dogs. Auditory disturbance induced by administration of 500mg/kg KM for 13 to 14 days to a dog was induced by sudden loss of ABR waves, when loss of pinna reflex was also noted in animals autopsied. Blood chemical examination revealed transient elevation of GOT, BUN, LDH, and CPK value. After recovery periods, in dogs treated with 125 and 250mg kg KM, the disorder of ABR remained unchanged. Histopathologically, loss of hair cells of the organ of Corti and degeneration of supporting cells were recognized at dose of 125, 250, and 500mg kg KM. Histological damage correlated well with the observed ABR changes. The present invesigation revealed usefulness of electrophysiological methods to detect ototoxicity in dogs.
