摘要
目的通过测试听性脑干反应和复合动作电位评估石杉碱甲对D-半乳糖致老年性聋大鼠听觉功能的改变。方法出生后3～4 W的Sprague-Dawley大鼠随机分为3组,模型组用5%D-半乳糖(200 mg/kg)行颈背部皮下连续注射8 W制备大鼠老年性聋模型;干预组用5%D-半乳糖(200 mg/kg)和石杉碱甲(0.1 mg/kg)行大鼠颈背部皮下注射;空白组作为对照。用药前、后分别检测大鼠听性脑干反应(auditory brainstem response,ABR)以检测听觉敏感性;复合动作电位(compound actionpotential,CAP)测试耳蜗输出幅度;以成对短声(pair clicks)为时间紧张性刺激,通过各CAP2/CAP2(20 ms)比值与短声间隔的关系函数反映耳蜗时间分辨能力。β-半乳糖苷酶染色下丘衰老细胞。结果 3组动物用药前后ABR阈值无明显改变(P>0.05);和模型组相比,干预组8kHz下80 dBSPL时ABRⅢ波潜伏期、I～V波间期缩短,提示听觉信号从外周到中枢的传入时间减少;以成对短声CAP响应所代表的耳蜗时间分辨力干预组高于模型组,但仍低于对照组;模型组下丘衰老细胞密度最高,干预组次之,对照组最少。结论石杉碱甲可以提高D-半乳糖致老年性聋大鼠与言语识别相关的听觉处理能力,为临床寻找改善老年患者听觉功能药物提供实验支持。
Objective To evaluate the effect of Huperzine A on auditory function of presbycusis rats induced by D-galactose through examinations of auditory brainstem response （ ABR ） and compound action potential （ CAP ）. Methods Postnatal 3-4 weeks SD rats were randomly divided into three groups. Rats in the model group were subcutaneously injected with 200 mg · kg-1 D-galactose daily for 8 weeks, and rats in the treatment group received both D-galactose （200 mg · kg-1 ） and Huperzine A （0. 1 mg · kg-1 ） as the same way as the model group. Normal saline of the same volume as that of the model group was applied to the animals of the control group. Auditory sensitivity was evaluated using ABR and cochlear output amplitude was assessed using CAP. CAP was also recorded in response to time-stress stimuli （paired clicks with varied stimulus interval, ISI ）. The cochlear temporal processing ability was reflected by the changes of ratio of CAP2/CAP2 （ 20 ms ） to the second click as a function of ISI. Results After interventions, the thresholds of ABR in all the three groups were insignificant changed （ P 〉 0.05 ）. However, compared with the model group, the ABR latencies of wave Ⅲ and Ⅰ-Ⅴ interpeak latencies in the treatment group were shortened. Correspondingly, CAP detection via paired click showed that sensitivity of temporal resolution in the treatment group was better than that of the model group, but worse than that of the control group. Meanwhile, the number of senile cells in the inferior colliculus in the treatment group was significantly less than that in the model group. Conclusions Huperzine A is likely to improve the auditory processing ability related to the speech recognition, which is the experimental support to look for the drug that can ameliorate the auditory function of presbycusis.
出处
《中国耳鼻咽喉颅底外科杂志》
CAS
2013年第3期199-203,共5页
Chinese Journal of Otorhinolaryngology-skull Base Surgery
