大鼠内耳拟老化伴线粒体突变模型的建立  

Establishment of model with inner ear mimetic aging and mtDNA 4834 bp deletion in rats

作　　者：孔维佳[1] 胡钰娟[1] 王琼[1] 许黎[1] 王莹[1] 韩月臣[1] 李隽[1] 刘波[1] 孔雯[1] 

机构地区：[1]华中科技大学同济医学院附属协和医院耳鼻咽喉科,武汉430022

出　　处：《临床耳鼻咽喉科杂志》2006年第19期888-890,893,共4页Journal of Clinical Otorhinolaryngology

基　　金：国家杰出青年基金项目(No:39925035);国家自然科学基金项目(No:30471878);国家十五科技攻关计划(No:2004BA720A18-02)

摘　　要：目的:探讨建立大鼠内耳拟老化伴线粒体突变模型,为进一步揭示老年性聋发病机制及其防治策略奠定基础。方法:Wistar大鼠24只,随机分为2组:A组14只,5%D-半乳糖颈部皮下注射(150mg·kg-1·d-1),共8周,继以生理盐水腹腔注射10d;B组10只,仅给予生理盐水注射。听性脑干反应(ABR)检测2组大鼠听阈,比色法检测2组大鼠膜迷路谷胱甘肽过氧化物酶(GSH-PX)活力。利用巢氏聚合酶链反应技术检测内耳组织线粒体DNA4834bp缺失突变的发生情况。结果:用药后A组大鼠线粒体DNA4834bp缺失突变发生率为100%(28/28),B组无线粒体DNA4834bp缺失突变检出。A组GSH-PX活力[(59.07±8.70)U]明显低于B组[(142.10±7.02)U],其差异具有统计学意义(P<0.01)。而A组ABR听阈平均提高(5.36±3.08)dBpeSPL,B组为(6.50±3.37)dBpeSPL,经t检验,A组和B组之间差异无统计学意义(P>0.05)。结论:D-半乳糖可以诱导大鼠内耳组织拟老化,此模型大鼠内耳组织线粒体DNA4834bp缺失突变率极高,但听阈无明显提高。Objective： To explore the establishment of the mimetic aging effect in the inner ear of the rat, Method：Twenty-four Wistar rats were randomly divided into two groups： group A （D-galactose group, n=14）, which were treated with hypodermic 5% D-galactose （ 150 mg·kg^-1·d^-1 ） for 8 weeks and then with intraperitoneal saline for 10 days, and group B （control group, n = 10）, which were given saline only. Auditory brainstem response（ABR） was used to detect the hearing threshold of rats, and colorimetry was used to analyze the activity of the glutathione peroxidase（GSH-PX）. The inner ear tissue was harvested and mitochondrial DNA was amplified to identify the 4834 bp deletion mutation by nested primer polymerase chain reaction （nested PCR） technique. Resuit：The incidence of mitochondrial DNA 4834 bp deletion of group A was100% （28/28） , while the deletion of group B was 0. The activity of the GSH-PX in group A（59.07±8.70 U） was lower than that in group B（142.10±7.02 U）. The difference between group A and group B was significant（t-test, P〈0.01）. Variation in ABR threshold of （5.36±3.08） dB peSPL was observed in group A, and （6.50±3.37） dB peSPL in group B. The difference in shift of ABR threshold between group A and group B was not significant（ P〉0.05）. Conclusion：The mimetic aging effect in the inner ear of the rat can be induced by D-galactose, and this rat model presents high incidence of mtDNA4834 deletion. But no hearing loss was found in this model.

关 键 词：内耳 老化 线粒体DNA 突变 疾病模型.动物 

分 类 号：R764.43[医药卫生—耳鼻咽喉科]