伐地那非对豚鼠噪声性聋治疗效果的初步观察

Preliminary Observation of Effects of Vardenafil on Noise-induced Hearing Loss in Guinea Pigs

目的探讨伐地那非(Vardenafil)对豚鼠噪声性聋治疗效果的影响。方法将45只豚鼠于白噪声中暴露3周,再随机分为Nacl注射组、伐地那非组和银杏叶片组,各15只。三组豚鼠在白噪声暴露3周后分别腹腔注射NaCl注射液4 mL/(kg·d)、伐地那非1 mg/(kg·d)、银杏叶(Ginkgo biloba tablet)1.92mg/(kg·d),连续给药4周。分别测试噪声暴露结束后及给药后1、2、4周听性脑干反应(ABR)阈值,并通过扫描电镜观察给药结束后豚鼠耳蜗毛细胞的形态变化。结果Nacl注射组在给药1周后、给药2周后及给药4周后较噪声暴露后ABR阈值呈延长趋势,伐地那非组和银杏叶组ABR阈值在给药1周后较噪声暴露后即出现不同程度下降,且伐地那非组较银杏叶组下降幅度大。扫描电镜显示,Nacl注射组豚鼠耳蜗外毛细胞出现听毛紊乱、融合及缺失;而伐地那非组及银杏叶组耳蜗病变均较对照组轻,听毛有不同程度的倒伏、融合现象。伐地那非组较银杏叶组病变轻。结论伐地那非能够减轻噪声性聋对豚鼠耳蜗毛细胞的损害,降低其引起的ABR升高,且其治疗噪声性聋的疗效优于银杏叶。

Objective To report effects of Vardenafil on noise-induced hearing loss in guinea pigs.Methods After exposure to white noise at 120 dB SPL for three weeks,45 guinea pigs were randomly divided into three groups to receive Nacl(4 ml/kg.d),Vardenafil(1 mg/kg.d)or Ginkgo biloba tablet(1.92 mg/kg.d)(n=15 in each group)for four weeks.Auditory brainstem responses(ABRs)were measured upon completion of noise exposure and at 1,2 and 4 weeks after treatment.Changes of cochlea hair cells were examined by scanning electron microscopy(SEM).Results ABR thresholds showed a trend of continued elevation following noise exposure in animals receiving NaCl but started to improve after one week of treatment in those on Vardenafil and Ginkgo biloba,especially in those on vardenafil(P<0.05).On scanning electron microscopy,outer hair cell sterocillia morphology abnormalities(bending,fusion and loss)were the most severe in animals receiving Nacl and the least so in those on vardenafil with only slight flattening and fusion.Conclusion Vardenafil appears to protect against noise-induced hearing damage in guinea pigs,preventing elevation of ABR thresholds,better than Ginkgo biloba.