Incorporation of Tetracycline into Otoconia of the Guinea-pig following Streptomycin Intoxication

The effects of streptomycin on the calcium ion turnover into otoconia of adult guinea-pigs investigated by the use of tetracycline. The oral administration of tetracycline induced the deposition of tetracycline (fluorescence) on the outer surface of otoconia indicating the existence of dynamic exchange and/or uptake of calcium ions in the otoconia. The significant finding is that streptomycin specifically interfered with calcium uptake into the otoconia which indicated that the decrease in calcium uptake caused by streptomycin may be closely related to the loss of otoconia as well as to a decrease in the calcium contents of otoconia. The decrease in calcium incorporation into otoconia caused by streptomycin was recovered within 6 weeks after the last injection of streptomycin. The number of otoconia with fluorescence in the central portion as well as their outer surface was increased. It is therefore suggested that the recovery of calcium uptake as well as new otoconial regeneration may play an important role for the recovery from loss of otoconia.