老龄大岳㈣能下降与线粒体DNA4834bp缺失突变的关系  

作　　者：黄海林 刘俊[2] 

机构地区：[1]浙江省金华市中心医院,321000 [2]浙江中医药大学附属第一医院,310006

出　　处：《浙江临床医学》2018年第9期1476-1478,共3页Zhejiang Clinical Medical Journal

基　　金：浙江省中医药管理局项目（2009CB017）;浙江省卫生厅项目（20098120）

摘　　要：目的探讨大鼠老年性耳聋与听觉器官线粒体DNA4834bp缺失突变的关系。方法取sD大鼠按年龄随机分为对照组（3个月龄）与观察组（24个月龄）．各10只。分别对2组大鼠进行听性脑干反应（ABR）测试听阈，采用PCR技术检测大鼠内耳耳蜗及蜗神经核组织线粒体DNA4834bp缺失突变情况，应用凝胶酶切电泳技术证实线粒体DNA缺失突变的存在。结果对照组大鼠ABR平均听阈为（19．50±3．69）dBpeSPL，观察组大鼠ABR平均听阀（46．00±3．94）dBpeSPL，两组差异有统计学意义（P〈005）。线粒体DNA大片段缺失检出情况：对照组大鼠内耳组织及蜗神经核未发现线粒体DNA4834bp缺失，观察组大鼠内耳组织线粒体DNA4834bp缺失突变检出率为90．O％，脑蜗神经核线粒体DNA4834bp缺失检出率为100％。结论老龄大鼠听觉器官（内耳组织和蜗神经核）线粒体DNA4834bp缺失突变检出率高，这种大片段缺失与老龄大鼠听功能下降密切相关。Objective To study the relationship between presbycusis and mitochondrial DNA 4834bp deletion in auditory organs.Methods 20 SD rats were randomly divided into young group （ young rat, 3months, n=10 ） and the aged group （ old rat, 24 months, n=10 ） according to the age. The threshold of the auditory brainstem response （ ABR ） was tested. Polymerase chain reaction （ PCR ） were performed to screen mitochondrial DNA4834bp deletions in the cochlea and cochlear nucleus of brain, then gel etectrophoresis technique was utilized to prove the presence of deletions. Results The mean of ABR thresholds in the aged group （ 46.00 ± 3.94dB peSPL ） was significantly higher than that in young group （ 19.50 ± 3.69dB peSPL ） （ P〈0.05 ） . The incidence of mitochondrial DNA 4834bp deletion in the aged group was 90.0% （ 9 rats/10 rats ） in inner ear tissue, 100% in cochlear nucleus of brain （ 10 rats / 10 rats ） , while no deletion was detected in young group. Conclusion Deletion of mtDNA4834bp in inner ear tissue and cochlear nucleus of brain is found in the aged rats, which is associated with the presbycusis and may be one of the causes ofpresbycusis.

关 键 词：缺失突变 线粒体DNA4834bp 老年性耳聋 内耳 蜗神经核 

分 类 号：R587.1[医药卫生—内分泌]