Farde L, Hall H, Pauli S, Halldin C
Karolinska Institutet, Department of Clinical Neuroscience, Stockholm, Sweden.
Synapse. 1995 Jul;20(3):200-8. doi: 10.1002/syn.890200303.
The variability of D2-dopamine receptor binding parameters in man was determined using Positron Emission Tomography (PET) and [11C]raclopride. A saturation analysis based on five PET-experiments was performed in each of ten men and ten women. The mean density of D2-dopamine receptors (Bmax) was 28 +/- 6.9 pmol/ml (mean +/- S.D.) and the apparent affinity (Kdapp) 9.1 +/- 1.9 pmol/ml. The Hill coefficient was in all subjects close to unity (nH: 0.999 +/- 0.020), thereby indicating binding to a homogeneous class of receptors. No significant differences between males and females were found in Bmax or Kdapp. The interindividual difference in Bmax was statistically significant (alpha = 0.01). The difference in Kdapp was not significant. Upregulation of the receptor density (Bmax) has been widely discussed as a mechanism for increased dopaminergic neurotransmission in schizophrenia. This study indicates that receptor density varies considerably in a group of healthy subjects.
利用正电子发射断层扫描（PET）和[11C]雷氯必利测定了人类D2-多巴胺受体结合参数的变异性。对10名男性和10名女性分别进行了基于5次PET实验的饱和分析。D2-多巴胺受体的平均密度（Bmax）为28±6.9 pmol/ml（平均值±标准差），表观亲和力（Kdapp）为9.1±1.9 pmol/ml。所有受试者的希尔系数均接近1（nH：0.999±0.020），这表明与一类同质受体结合。在Bmax或Kdapp方面，未发现男性和女性之间存在显著差异。Bmax的个体间差异具有统计学意义（α = 0.01）。Kdapp的差异不显著。受体密度（Bmax）的上调作为精神分裂症中多巴胺能神经传递增加的一种机制已被广泛讨论。这项研究表明，在一组健康受试者中，受体密度存在相当大的差异。
