老年大鼠大脑皮质、海马和小脑的线粒体DNA缺失突变  

Mitochondrial DNA Deletion in the Cerebral Cortex, Hippocampus and Cerebellum of the Aged Rats

作　　者：项平[1] 高国全[1] 周丽华[1] 姚志彬[1] 

机构地区：[1]中山医科大学脑研究室,广东广州510089

出　　处：《中山医科大学学报》2000年第1期10-13,共4页Academic Journal of Sun Yat-sen University of Medical Sciences

基　　金：国家自然科学基金!资助课题 (39670 2 4 4 )

摘　　要：目的】测定老年大鼠脑缺失型mtDNA比例,探讨mtDNA缺失与脑衰老的关系,为研究其分子机制提供基础资料。【方法】用碱裂解法抽提青年(3个月)SD大鼠10只和老年(24个月)SD大鼠17只的大鼠皮质、海马和小脑的mtDNA。稀释PCR法测mtDNA的缺失比例。【结果】青年鼠和老年鼠大脑皮质、海马和小脑均存在缺失型mtDNA,缺失片段为4834bp。青年鼠各脑区缺失型mtDNA比例分别为0000156%、0000148%、0000152%;老年鼠上述3个脑区缺失型mtDNA比例分别是0001446%、0001484%、0000987%,是青年鼠的9、10和65倍。【结论】衰老时脑缺失型mtDNA比例增多,以海马的mtDNA缺失增多最为显著。提示mtDNA缺失可能是神经元衰老性退变的主要因素之一。Objective By measuring the ratio of mtDNA deletion of brain tissue, the relationship between mtDNA deletion and brain aging would be found in order to explain the molecular mechanism of aging. Method The mtDNA of the cerebral cortex, hippocampus and cerebellum of ten young (3 months) and seventeen aged (24 months) SD rats were isolated by alkaline extraction. The ratio of mtDNA deletion was measured by serial dilution PCR. Result The 4 834 bp deletion in mtDNA was found in the brain tissue of young and aged rats. The ratios of deleted mtDNA were similar in the cerebral cortex, hippocampus, cerebellum of young rats (0 000 156%,0 000 148%,0 000 152%). The ratios of aged rats increased by 9,10 and 6 5 fold in the three brain regions over young rats. Conclusions mtDNA deletion also accumulated in the aged rat brain. It suggests that the accumulation of deleted mtDNA may be one of important factors of neuronal degeneration with aging.

关 键 词：线粒体DNA缺失 基因缺失 衰老 大脑皮质 海马 

分 类 号：R338.2[医药卫生—人体生理学] R339.38[医药卫生—基础医学]