电针耳穴对D-半乳糖致年龄相关性听力损失豚鼠听觉中枢丙二醛表达的影响

目的探讨丙二醛在豚鼠年龄相关性听力损失发病中的作用和电针对年龄相关性听力损失的防治作用及机制。方法 4月龄豚鼠30只分为三组,每组10只,D-半乳糖模型组:豚鼠颈背部皮下注射D-半乳糖300mg.kg-1.d-1,每日1次,连续注射6周;D-半乳糖+电针组:D-半乳糖的用法用量同模型组,同时电针刺听宫、翳风两个穴位;对照组:给予等量生理盐水颈背部皮下注射,每天1次,连续6周。2年龄豚鼠10只(老年组)自然喂养。实验结束后各组行ABR检测,采用硫代巴比妥酸法(TBA)检测听皮层、下丘和耳蜗核组织中丙二醛的表达。结果①D-半乳糖模型组ABR波Ⅲ潜伏期比对照组延长(P<0.05);D-半乳糖+电针组ABR波Ⅲ潜伏期比D-半乳糖模型组缩短(P<0.05);②D-半乳糖模型组和老年组豚鼠听皮层、下丘和耳蜗核丙二醛含量明显高于对照组(P<0.05);与D-半乳糖模型组相比,D-半乳糖+电针组三个部位的丙二醛含量显著降低(P<0.05),但D-半乳糖模型组与老年组相比无明显差异(P>0.05)。结论豚鼠听觉中枢的老化可能与丙二醛含量升高所导致的脂质过氧化有关;针刺听宫和翳风两个穴位可通过降低丙二醛的表达,在一定程度上抑制D-半乳糖所致的豚鼠听觉中枢的老化过程。

Effects of Electroacupuncture at Tinggong and Yifeng on MDA Expression in Auditory Center of Guinea Pigs with Age-related Hearing Loss by D-galactose

Objective To investigate the effects of malondialdehyde(MDA),and the effects and mechanisms of electroacupuncture on auditory center of guinea pigs with age-related hearing loss(AHL) by D-galactose. Methods Thirty of 2-month-old guinea pigs were divided into 3 groups.The guinea pigs of the D-galactose and electroacupuncture(DE,n=10),and D-galactose groups(n=10) were subcutaneously injected D-galactose(300 mg/kg.day),and the DE group were electroacupunctured at Tingggong and Yifeng for 6weeks.The control group(CG,n=10) was injected the same dose of physiological saline.The fourth group included 10 of 2-year-old guinea pigs.After 6 weeks,ABR were tested,and MDA expression in auditory cortex,inferior colliculus and cochlear nucleus of all guinea pigs were quantitated by the TBA method.The data were analyzed using analysis of variance. Results 1.There was a significant increase in the average latent period of the third wave of ABR of the DG(P<0.05,compared with the CG),and decrease in the DEG(P<0.05,compared with the DG).2.There was an increase in MDA expression of the auditory cortex,inferior colliculus and cochlear nucleus in the DG and 2-year-old group(P<0.05,compared with the CG),a decrease in the DEG(P<0.05,compared with the DG),and no significant changes in the 2-year-old group(P<0.05,compared with the DG). Conclusion The aging of the auditory center would be related with the lipid peroxidation induced by the increase of MDA.Electroacupuncture at Tingggong and Yifeng of the guinea pig maybe effective partly inhibit the aging process of the auditory center.