Background Ouabain, a cardiac glycoside that specifically binds to Na/K-ATPase and inhibits its activity, was applied to gerbils to develop a method for studying auditory neuropathy. Methods Ouabain was applied to the...Background Ouabain, a cardiac glycoside that specifically binds to Na/K-ATPase and inhibits its activity, was applied to gerbils to develop a method for studying auditory neuropathy. Methods Ouabain was applied to the round window of the cochlea in each gerbil by using a piece of gelfoam with 3 μl or 24 μl (1 mmol/L) ouabain solution. The changes of the threshold of auditory brainstem response, cochlear function round window electrocochleography, as well as the morphological changes of the spiral ganglion cells of the cochlea were observed after application of ouabain for 24 hours or 96 hours. Results In ouabain treated gerbils, auditory brainstem response and compound action potential thresholds showed either elevation or no response at all. However, the thresholds of cochlear microphonic and distortion product otoacoustic emissions were not affected. Degeneration and necrosis of some spiral ganglion cells in ears with applications of ouabain (24 hours, 3 μl, 1 mmol/L; 96 hours, 24 μl, 1 mmol/L ouabain). The number of spiral ganglion cells was decreased (24 hours, 3 μl, 1 mmol/L ouabain) or near to a total loss (96 hours, 24 μl, 1 mmol/L ouabain).Conclusions These results indicate a high degree of independence between the spiral ganglion ceils and the outer hair cell systems in the cochlear transduction mechanism. The method used in this study would provide a valuable tool for studying auditory neuropathy.展开更多
To the editor: Cochlear implantation (CI) has been successfully performed in patienls with severe to profound sensorineural hearing loss (SNHL) worldwide since 1988. CI has been demonstrated to be effective for a...To the editor: Cochlear implantation (CI) has been successfully performed in patienls with severe to profound sensorineural hearing loss (SNHL) worldwide since 1988. CI has been demonstrated to be effective for aural rehabilitation in patients with bilateral temporal bone fractures. The 28-year-old patient was first seen in our clinic in June 2009 coinplaining of bilateral hearing loss, left facial nerve palsy, and cerebrospinal fluid (CSF) leak in his left ear fbflowing temporomandibular .ioint (TMJ) surgery lor ankylosis three months earlier. He was diagnosed as having TMJ ankylosis when he was 6 years old;展开更多
文摘Background Ouabain, a cardiac glycoside that specifically binds to Na/K-ATPase and inhibits its activity, was applied to gerbils to develop a method for studying auditory neuropathy. Methods Ouabain was applied to the round window of the cochlea in each gerbil by using a piece of gelfoam with 3 μl or 24 μl (1 mmol/L) ouabain solution. The changes of the threshold of auditory brainstem response, cochlear function round window electrocochleography, as well as the morphological changes of the spiral ganglion cells of the cochlea were observed after application of ouabain for 24 hours or 96 hours. Results In ouabain treated gerbils, auditory brainstem response and compound action potential thresholds showed either elevation or no response at all. However, the thresholds of cochlear microphonic and distortion product otoacoustic emissions were not affected. Degeneration and necrosis of some spiral ganglion cells in ears with applications of ouabain (24 hours, 3 μl, 1 mmol/L; 96 hours, 24 μl, 1 mmol/L ouabain). The number of spiral ganglion cells was decreased (24 hours, 3 μl, 1 mmol/L ouabain) or near to a total loss (96 hours, 24 μl, 1 mmol/L ouabain).Conclusions These results indicate a high degree of independence between the spiral ganglion ceils and the outer hair cell systems in the cochlear transduction mechanism. The method used in this study would provide a valuable tool for studying auditory neuropathy.
文摘To the editor: Cochlear implantation (CI) has been successfully performed in patienls with severe to profound sensorineural hearing loss (SNHL) worldwide since 1988. CI has been demonstrated to be effective for aural rehabilitation in patients with bilateral temporal bone fractures. The 28-year-old patient was first seen in our clinic in June 2009 coinplaining of bilateral hearing loss, left facial nerve palsy, and cerebrospinal fluid (CSF) leak in his left ear fbflowing temporomandibular .ioint (TMJ) surgery lor ankylosis three months earlier. He was diagnosed as having TMJ ankylosis when he was 6 years old;