Ito H, Okubo Y, Halldin C, Farde L
Department of Clinical Neuroscience, Karolinska Hospital, Stockholm, Sweden.
Neuroimage. 1999 Feb;9(2):235-42. doi: 10.1006/nimg.1998.0401.
D2 dopamine receptors are of interest in the pathophysiology of schizophrenia. For group comparisons of neuroreceptor distribution measured by PET on a pixel-by-pixel basis, an anatomic standardization technique is required. The aim of the present study is to build a database of normal D2 dopamine receptor distribution using [11C]raclopride and an anatomic standardization technique. In each subject, two PET measurements were performed with rapid bolus injection and with continuous infusion of [11C]raclopride. The radioactivity of the PET images were integrated in the time interval. Integrated images were normalized by the radioactivity of the cerebellum, providing a measure of the binding potential (BP) in each pixel. Each PET image was transformed into a standard brain anatomy using a Computerized Brain Atlas system. From the standardized PET images, the sample mean and the SD of the BP were calculated in each pixel. On the anatomically standardized average images for the both rapid bolus injection and continuous infusion, high BP was observed in the putamen and the caudate nucleus, whereas low BP was observed in the cerebral cortices. The BP for the thalamus and the substantia nigra were slightly higher than those for the cerebral cortices. This regional distribution is in good agreement with the distribution of D2 dopamine receptors known from in vitro studies. The anatomic standardization technique permits to build a database of the normal D2 dopamine receptor distribution in the living human brain. This technique can be applied for group comparisons on a pixel-by-pixel basis.
D2多巴胺受体在精神分裂症的病理生理学中备受关注。对于通过PET逐像素测量神经受体分布的组间比较，需要一种解剖标准化技术。本研究的目的是使用[11C]雷氯必利和解剖标准化技术建立一个正常D2多巴胺受体分布的数据库。在每个受试者中，通过快速推注和持续输注[11C]雷氯必利进行两次PET测量。在时间间隔内对PET图像的放射性进行积分。积分图像通过小脑的放射性进行归一化，从而提供每个像素中结合潜能（BP）的测量值。使用计算机脑图谱系统将每个PET图像转换为标准脑解剖结构。从标准化的PET图像中，计算每个像素中BP的样本均值和标准差。在快速推注和持续输注的解剖标准化平均图像上，壳核和尾状核观察到高BP，而在大脑皮层观察到低BP。丘脑和黑质的BP略高于大脑皮层。这种区域分布与体外研究已知的D2多巴胺受体分布高度一致。解剖标准化技术允许建立活体人脑中正常D2多巴胺受体分布的数据库。该技术可用于逐像素的组间比较。
