Brain dopamine D-1 receptors in senile dementia

Brain dopamine D-1 binding sites were studied by using [3H]flupenthixol in 4 brain regions of 44 senile patients with neuropathologically verified organic dementia and 28 age-matched controls. The D-1 binding sites were decreased in the substantia nigra and nucleus accumbens in patients with Alzheimer's disease, while no change was found in multi-infarct or combined dementia. The striatal D-1 binding sites were unchanged in all groups of patients. Only a few correlations between various clinical and post-mortem variables and the [3H]flupenthixol binding of the dementia patients were found. The findings of this study indicate that there is reduction of brain D-1 binding sites in patients with Alzheimer's disease.