Figure 5.

Quantitative autoradiographic analysis of dopamine D1 receptor (D1R) density in the caudate and putamen of patients with diseases [Parkinson disease (PD): n = 10, Parkinson disease dementia (PDD): n = 7, dementia with Lewy bodies (DLB): n = 10, Alzheimer's disease (AD): n = 26] and age‐matched controls (n = 10). (a) Quantitative analysis of the D1R density (fmol/mg) in the caudate and putamen of subjects. Value shown are means ± SEM. Statistical significances between two disease groups are indicated with brackets and corresponding p‐values [Caudate: PD vs AD (p = 0.0021); Putamen: PD vs AD (p = 0.0005), PDD vs AD (p = 0.0004), DLB vs AD (p = 0.0041)]. A p value of < 0.05 was considered significant: ** indicates p < 0.01, *** indicates p < 0.001, vs. the controls. (b) Autoradiograms show total binding of 1.5 nM [³H]SCH23390 (Panel b top row) and non‐specific binding in the presence of 1 µM (+) butaclamol (Panel b bottom row) in the striatal regions of the same 5 representative subjects. The numbers 1 and 2 designate the following regions: caudate (1) and putamen (2). (c) [³H]Microscale standards (ranging from 0 to 36.3 nCi/mg) were also counted.