Acute and chronic effects of streptomycin applied to the lateral semicircular canal.
In developing the technique of selective chemical vestibulectomy, the destructive effect of streptomycin on the hair cells of the inner ear was well established. However, in both animal and human studies, a rapid onset of the drug's vestibular inhibition was observed in addition to a more slowly developing long-term destructive effect. In previous laboratory studies, streptomycin had been given only by a systemic route, and only the chronic long-term effects had been observed. In this study, an isolated semicircular canal was prepared and streptomycin was placed into the perilymph bathing the canal. The spontaneous and evoked afferent nerve activity were recorded prior to streptomycin application, during application, and after a washout period. During streptomycin application, the activity of the semicircular canal was reversibly inhibited in a dose dependent manner. After a sufficient washout period (5-10 min), the preparation had completely recovered from the drug's effect. Thus, there are two phases in the vestibular inhibition by streptomycin: an early reversible phase that subsequently can transform into a later irreversible phase.
Norris
C H
CH
Tulane University School of Medicine, Department of Otolaryngology-Head and Neck Surgery, New Orleans, Louisiana.
Aubert
A
A
Amedee
R G
RG
D000818:Animals; D002121:Calcium Channel Blockers / Q000378:metabolism / Q000493:pharmacokinetics; D004110:Diltiazem / Q000378:metabolism / Q000493:pharmacokinetics; D004566:Electrodes; D006198:Hair Cells, Auditory / Q000187:drug effects; D066298:In Vitro Techniques; D011894:Rana pipiens; D012665:Semicircular Canals / Q000166:cytology / Q000187:drug effects*; D013307:Streptomycin / Q000008:administration & dosage / Q000009:adverse effects / Q000494:pharmacology*; D014722:Vestibule, Labyrinth / Q000187:drug effects*
D002121:Calcium Channel Blockers; D004110:Diltiazem; D013307:Streptomycin