Buckner Randy L, Snyder Abraham Z, Shannon Benjamin J, LaRossa Gina, Sachs Rimmon, Fotenos Anthony F, Sheline Yvette I, Klunk William E, Mathis Chester A, Morris John C, Mintun Mark A
Howard Hughes Medical Institute, Washington University School of Medicine, St. Louis, Missouri 63105, USA.
J Neurosci. 2005 Aug 24;25(34):7709-17. doi: 10.1523/JNEUROSCI.2177-05.2005.
Alzheimer's disease (AD) and antecedent factors associated with AD were explored using amyloid imaging and unbiased measures of longitudinal atrophy in combination with reanalysis of previous metabolic and functional studies. In total, data from 764 participants were compared across five in vivo imaging methods. Convergence of effects was seen in posterior cortical regions, including posterior cingulate, retrosplenial, and lateral parietal cortex. These regions were active in default states in young adults and also showed amyloid deposition in older adults with AD. At early stages of AD progression, prominent atrophy and metabolic abnormalities emerged in these posterior cortical regions; atrophy in medial temporal regions was also observed. Event-related functional magnetic resonance imaging studies further revealed that these cortical regions are active during successful memory retrieval in young adults. One possibility is that lifetime cerebral metabolism associated with regionally specific default activity predisposes cortical regions to AD-related changes, including amyloid deposition, metabolic disruption, and atrophy. These cortical regions may be part of a network with the medial temporal lobe whose disruption contributes to memory impairment.
利用淀粉样蛋白成像和纵向萎缩的无偏测量方法，并结合对先前代谢和功能研究的重新分析，探索了阿尔茨海默病（AD）及其相关的前驱因素。总共对764名参与者的数据进行了五种活体成像方法的比较。在后皮质区域观察到了效应的汇聚，包括后扣带回、压后皮质和顶叶外侧皮质。这些区域在年轻人的默认状态下是活跃的，并且在患有AD的老年人中也显示出淀粉样蛋白沉积。在AD进展的早期阶段，这些后皮质区域出现了明显的萎缩和代谢异常；内侧颞叶区域也观察到了萎缩。事件相关功能磁共振成像研究进一步表明，这些皮质区域在年轻人成功进行记忆检索时是活跃的。一种可能性是，与区域特异性默认活动相关的终生脑代谢使皮质区域易发生与AD相关的变化，包括淀粉样蛋白沉积、代谢紊乱和萎缩。这些皮质区域可能是与内侧颞叶相连的网络的一部分，该网络的破坏会导致记忆障碍。
