CLINICAL INVESTIGATIONS Regional Cerebral Blood Flow Response to Oral Amphetamine Challenge in Healthy Volunteers

Functional brain imaging is a powerful tool for examining the central nervous system (CNS) response to pharmacologic chal-lenges. Amphetamine is of interest both because of its role as a stimulant of the dopaminergic system and because of its use to alter mood in mood-disordered patients, particularly in patients suffering from depression. In this study, we report the effects of oral d-amphetamine relative to placebo on regional cerebral blood flow (rCBF) measured by SPECT in healthy volunteers to characterize the normal CNS response to this primarily dopa-minergic stimulant. Methods: SPECT was used to assess changes in rCBF induced by amphetamine in 16 healthy volun-teers. Subjects received placebo and then 0.4 mg/kg oral am-phetamine in a fixed-order single-blind design and were imaged on a triple-head tomograph. Another six healthy volunteers received placebo at both times to assess normal rCBF variabil