Regional uptake of radioactivity in monkey brain after the administration of [11C]3 under baseline conditions (Panel A), and at 30 min after the intravenous administration of DCPQ (8 mg/kg, i.v.) (Panel B). Key: temporal cortex (○), cerebellum (□), putamen (×) and pituitary (●). In Panel A, data for putamen lie between those of temporal cortex and cerebellum (not shown for Figure clarity). Frontal and parietal cortical regions gave curves similar to those of temporal cortex under each condition.