Gill Gia, Blakley Brian W
Department of Otolaryngology-Head and Neck Surgery, University of Manitoba, Winnipeg, Canada.
OTO Open. 2022 May 17;6(2):2473974X221100545. doi: 10.1177/2473974X221100545. eCollection 2022 Apr-Jun.
To assess whether multiple injections of a powerful antioxidant can improve established sensorineural hearing loss in guinea pigs.
Animal study.
Animal science laboratory, University of Manitoba.
A total of 16 guinea pigs were used in our study: 8 underwent unilateral intracochlear neomycin injection, and 8 underwent unilateral saline to serve as controls. After a period of 3 weeks for hearing loss to stabilize, 4 guinea pigs from each group received weekly intraperitoneal injections of N-acetylcysteine (NAC) for 4 weeks. Click auditory brainstem response (ABR) testing was conducted at baseline, weekly after the start of NAC injections, and after the last injection. Pure tone ABR tests were conducted prior to intracochlear injections and at completion of the study.
Click ABR thresholds were significantly worse in ears treated with neomycin ( < .001), as expected, but not significantly different when treated with NAC ( = .664). Thresholds for pure tone ABR were also not statistically different in neomycin-treated ears with or without NAC ( > .99).
The aggressive antioxidant therapy performed in this study was not successful in improving established hearing loss via an antioxidant regimen that is known to change the oxidation-reduction potential in the cochlea.
评估多次注射一种强效抗氧化剂是否能改善豚鼠已有的感音神经性听力损失。
动物研究。
曼尼托巴大学动物科学实验室。
本研究共使用16只豚鼠：8只接受单侧鼓室内注射新霉素，8只接受单侧注射生理盐水作为对照。在听力损失稳定3周后，每组4只豚鼠每周接受腹腔注射N-乙酰半胱氨酸（NAC），共4周。在基线、开始注射NAC后每周以及最后一次注射后进行短声听觉脑干反应（ABR）测试。在鼓室内注射前和研究结束时进行纯音ABR测试。
正如预期的那样，新霉素治疗的耳朵短声ABR阈值明显更差（P<0.001），但用NAC治疗时无显著差异（P=0.664）。新霉素治疗的耳朵无论是否使用NAC，纯音ABR阈值在统计学上也无差异（P>0.99）。
本研究中采用的积极抗氧化治疗未能通过已知可改变耳蜗氧化还原电位的抗氧化方案成功改善已有的听力损失。
