[西地那非对豚鼠噪声性听力损失中听性脑干反应阈值变化的影响]

Zhang Shu-jun, Zhang Xun, Liang Yuan, Yue Zhuo-li

Department of Otorhinolaryngology, Affiliated Hospital of Chengde Medical College, Chengde 067000, China.

Zhonghua Er Bi Yan Hou Tou Jing Wai Ke Za Zhi. 2011 Oct;46(10):844-7.

OBJECTIVE

To investigate the protective effects of sildenafil to noise-induced hearing loss in guinea pigs.

METHODS

Guinea pigs were randomly divided into control group, noise exposure group and the sildenafil treatment group, with 10 in each group. One week after the exposure of 110 dB (A) white noise, sildenafil [10 mg/(kg×d)] and normal saline [4 ml/(kg×d)] were injected into guinea pigs of noise plus sildenafil group (NSG) and noise plus normal saline group(NNG) respectively. One week after noise exposure to four weeks continuous administration. ABR thresholds were measured respectively prior to the experiment, 1 week post-noise, 1, 2 and 4 weeks post-drugs. The changes of cochlea hair cells were also observed by scanning electron microscope (SEM).

RESULTS

After noise exposure, the ABR threshold shifts in NSG were significantly fewer than that in the NNG. An average of 19.1 dB in NNG compared with 19.8 dB in NSG. Four weeks after exposure, the threshold shifts were become larger to 22.0 dB in NNG while become smaller to 4.8 dB in NSG. Compared NNG with NSG, in addition to noise exposure time point, there were statistically significant differences in the rest time points after administration of the ABR threshold (P<0.05). SEM showed that the inner and outer hair cells in NNG displayed mess, fusion and imperfections. In NSG, the hair cells displayed slight pathological changes, there was no significant difference when compared with control group.

CONCLUSION

Sildenafil is able to reduce the ascending of ABR thresholds shift, and it can significantly protect against noise-induced hearing loss.

目的

探讨西地那非对豚鼠噪声性听力损失的保护作用。

方法

将豚鼠随机分为对照组、噪声暴露组和西地那非治疗组，每组10只。在暴露于110 dB（A）白噪声1周后，分别向噪声加西地那非组（NSG）和噪声加生理盐水组（NNG）的豚鼠注射西地那非[10 mg/（kg×d）]和生理盐水[4 ml/（kg×d）]。噪声暴露1周后连续给药4周。分别在实验前、噪声暴露后1周、给药后1、2和4周测量ABR阈值。还通过扫描电子显微镜（SEM）观察耳蜗毛细胞的变化。

结果

噪声暴露后，NSG组的ABR阈值变化明显少于NNG组。NNG组平均变化19.1 dB，而NSG组为19.8 dB。暴露4周后，NNG组的阈值变化增大至22.0 dB，而NSG组减小至4.8 dB。与NSG组相比，除噪声暴露时间点外，给药后其余时间点ABR阈值差异均有统计学意义（P<0.05）。SEM显示，NNG组的内、外毛细胞排列紊乱、融合且有缺陷。NSG组毛细胞有轻微病理改变，与对照组相比无明显差异。