Rinne J O, Hietala J, Ruotsalainen U, Säkö E, Laihinen A, Någren K, Lehikoinen P, Oikonen V, Syvälahti E
Department of Neurology, University of Turku, Finland.
J Cereb Blood Flow Metab. 1993 Mar;13(2):310-4. doi: 10.1038/jcbfm.1993.39.
The effect of age on human striatal dopamine D2 receptors was investigated with positron emission tomography (PET) using [11C]raclopride as a radioligand. Twenty-one healthy volunteers aged from 20 to 81 years were studied. An equilibrium method was applied and two separate PET scans with different specific activities of [11C]raclopride were performed. The maximal number of receptors (Bmax) and their dissociation constant (Kd) were calculated using Scatchard analysis. There was an age-dependent decline in the Bmax (r = -0.49; p = 0.02) of striatal D2 receptors while the Kd remained unchanged. The results show that there is an age-related loss of striatal D2 receptors, which, together with other changes in the brain nigrostriatal dopaminergic system, may contribute to extrapyramidal symptoms associated with aging.
采用正电子发射断层扫描（PET）技术，以[11C]雷氯必利作为放射性配体，研究年龄对人类纹状体多巴胺D2受体的影响。研究对象为21名年龄在20至81岁之间的健康志愿者。采用平衡法，用不同比活度的[11C]雷氯必利进行了两次独立的PET扫描。使用Scatchard分析计算受体的最大数量（Bmax）及其解离常数（Kd）。纹状体D2受体的Bmax随年龄增长而下降（r = -0.49；p = 0.02），而Kd保持不变。结果表明，纹状体D2受体存在与年龄相关的丢失，这与脑黑质纹状体多巴胺能系统的其他变化一起，可能导致与衰老相关的锥体外系症状。
