增龄对大鼠心肌线粒体DNA氧化损伤的影响  

Influence of age on oxidative damage of mitochondrial DNA in rat heart

作　　者：王学美[1] 富宏[1] 刘庚信[1] 

机构地区：[1]北京大学第一医院中西医结合研究所,北京100034

出　　处：《中国老年学杂志》2003年第9期592-593,共2页Chinese Journal of Gerontology

基　　金：国家自然科学基金资助项目 (3980 0 1 99)

摘　　要：目的　探讨增龄对大鼠心肌线粒体 DNA(mt DNA)缺失、线粒体呼吸链酶复合体及 ATP合成的影响。方法　 Wistar雄性大鼠分为 3组 :幼年组 (1月龄 )、青年组 (6月龄 )各 1 2只和老年组 (2 4月龄 ) 1 0只。心肌线粒体 DNA缺失、线粒体呼吸链酶复合体及腺苷三磷酸 (ATP)合成分别用聚合酶链反应 (PCR)、酶动力学和生物发光技术进行测定。结果　 3组大鼠均有不同程度 mt DNA缺失。老年组 mt DNA缺失 (2 .0 9± 1 .62 )较幼年组 mt DNA缺失 (0 .77± 1 .1 6)明显增高 (P<0 .0 5) ;较青年组 mt DNA缺失 (1 .54± 1 .1 7)也有升高的趋势 (P>0 .0 5)。老年组心线粒体呼吸链复合酶 活力 (2 347.2 1± 62 3.33)均较青年组 (3 859.1 2± 70 3.53)、幼年组 (4776.90± 548.63)明显降低 (P<0 .0 1 )。老年组心线粒体 ATP合成量 (1 96.95± 33.2 6)较青年组 (337.53± 62 .1 8)明显降低 (P<0 .0 1 )。心线粒体呼吸链复合酶 活力 3组间无明显性差异 (P>0 .0 5)。结论　大鼠线粒体 DNA氧化损伤与衰老有一定的相关性。Objective To investigate the difference of mitochondrial DNA(mtDNA) deletions,respiratory chain enzyme complexes and ATP synthesis in rat heart of various ages.Methods Wistar rats were divided into three groups.namely infant rats(1 month),young rats(6 months) and aged rats(24 months). mtDNA deletions , respiratory chain enzyme complexes and ATP synthesis were divided determined with polymerase chain reaction(PCR),enzyme kinetics and bioluminescence technique.Results The deletion of mtDNA was present at different leveles in 3 groups. the relative deletion of mtDNA in heart of aged group(2.09 ±1.62) increased as comparde with infant group(0.77±1.16) (P<0.05). the activities of mitochondrial respiratory enzyme chain complexesⅣ in heart of aged group (2347.21±623.33)decreased as comparde with infant group(4776.90±548.63) and young group(3859.12±703.53) (P< 0.01).the ATP synthes in heart of aged group (196.95±33.26)also decreased as comparde with young group(337.53±62.18) (P< 0.01). the activities of mitochondrial respiratory chain enzyme complexesⅠis no significant difference in three group(P>0.05).Conclusions The study demonstrates relative relation between oxidative damage of mitochondrial DNA and aging.

关 键 词：大鼠 心肌线粒体DNA 氧化损伤 衰老 聚合酶链反应 自由基 

分 类 号：R339.38[医药卫生—人体生理学]