title: Positron emission tomography demonstrates dopamine D2 receptor supersensitivity in the striatum of patients with early Parkinson's disease.
abstract: Striatal dopamine D2 receptor binding was studied in vivo with positron emission tomography in seven patients with early Parkinson's disease using [11C]-raclopride. The patients had unilateral symptoms and none of them had received levodopa treatment. The accumulation of [11C]-raclopride in the striatum was rapid and reached a steady state at approximately 40 min after injection. The binding of [11C]-raclopride was measured in the striatum and cerebellum: The total striatal radioactivity in both hemispheres was counted and the respective striatum/cerebellum ratios were calculated. The striatum/cerebellum ratio of [11C]-raclopride binding was significantly (p less than 0.01) increased in the hemisphere contralateral to the parkinsonian symptoms as compared with the opposite hemisphere. Thus, this study demonstrates that there is denervation supersensitivity in dopamine D2 receptor binding in early Parkinson's disease.
authors: Department of Neurology, University of Turku, Finland.
authors: U K
authors: UK
authors: Rinne
authors: A
authors: A
authors: Laihinen
authors: J O
authors: JO
authors: Rinne
authors: K
authors: K
authors: Någren
authors: J
authors: J
authors: Bergman
authors: U
authors: U
authors: Ruotsalainen
mesh_terms: D000328:Adult; D000368:Aged; D003342:Corpus Striatum / Q000000981:diagnostic imaging / Q000378:metabolism*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010302:Parkinson Disease, Secondary / Q000000981:diagnostic imaging / Q000378:metabolism*; D020891:Raclopride; D011954:Receptors, Dopamine / Q000378:metabolism*; D017448:Receptors, Dopamine D2; D012457:Salicylamides / Q000378:metabolism*; D014055:Tomography, Emission-Computed
chemical_list: D011954:Receptors, Dopamine; D017448:Receptors, Dopamine D2; D012457:Salicylamides; D020891:Raclopride