Wang Y, Chan G L, Holden J E, Dobko T, Mak E, Schulzer M, Huser J M, Snow B J, Ruth T J, Calne D B, Stoessl A J
Neurodegenerative Disorders Centre and UBC-TRIUMF PET Group, Vancouver Hospital, UBC site, British Columbia, Canada.
Synapse. 1998 Sep;30(1):56-61. doi: 10.1002/(SICI)1098-2396(199809)30:1<56::AID-SYN7>3.0.CO;2-J.
Radioligand binding studies in animals have demonstrated age-related loss of dopamine receptors in the caudate and putamen. In humans, while age-related declines in dopamine D2 receptors have been consistently reported, the effects of ageing on D1 receptors have been controversial. We used positron emission tomography (PET) with [11C]SCH 23390 to investigate dopamine D1 receptor binding in 21 normal volunteers aged 22-74 years. We also assessed their motor function with a Modified Columbia Score (MCS) and the Purdue Pegboard Test (PPBT). D1 binding potentials were derived using a graphical analysis with a cerebellar tissue input function. Standard linear regression techniques were used to determine the age-related rate of decline of D1 binding. We found an age-dependent decrease of D1 receptor binding in the caudate (6.9% per decade) and putamen (7.4% per decade). There was also a significant inverse correlation between [11C]SCH 23390 binding in the occipital cortex and age (8.6% decline per decade). PPBT score also decreased with age (P = 0.007). There was a direct correlation between PPBT score and D1 binding potential. We conclude that dopamine D1 receptor density declines with age and that the effects of physiological ageing may play a role in the expression of extrapyramidal disorders in the elderly.
对动物进行的放射性配体结合研究表明，尾状核和壳核中的多巴胺受体存在与年龄相关的损失。在人类中，虽然一直有报道称多巴胺D2受体存在与年龄相关的下降，但衰老对D1受体的影响一直存在争议。我们使用[11C]SCH 23390进行正电子发射断层扫描（PET），以研究21名年龄在22至74岁之间的正常志愿者的多巴胺D1受体结合情况。我们还使用改良哥伦比亚评分（MCS）和普渡钉板测试（PPBT）评估了他们的运动功能。D1结合潜能通过使用小脑组织输入函数的图形分析得出。使用标准线性回归技术来确定D1结合与年龄相关的下降速率。我们发现，尾状核中D1受体结合随年龄下降（每十年下降6.9%），壳核中也是如此（每十年下降7.4%）。枕叶皮质中[11C]SCH 23390结合与年龄之间也存在显著的负相关（每十年下降8.6%）。PPBT评分也随年龄下降（P = 0.007）。PPBT评分与D1结合潜能之间存在直接相关性。我们得出结论，多巴胺D1受体密度随年龄下降，生理衰老的影响可能在老年人锥体外系疾病的表现中起作用。
