TY - JOUR T1 - A preliminary report of an <em>in vivo</em> investigation of amphetamine-induced dopamine release in schizophrenia. JF - Journal of Nuclear Medicine JO - J Nucl Med SP - 1630 LP - 1630 VL - 56 IS - supplement 3 AU - James Brasic AU - Thomas Sedlak AU - Anil Mathur AU - Ahmet Dogan AU - Ayon Nandi AU - Rebecca Mellinger-Pilgrim AU - Kelly Kitzmiller AU - Gerhard Gruender AU - Albert Gjedde AU - Dean Wong Y1 - 2015/05/01 UR - http://jnm.snmjournals.org/content/56/supplement_3/1630.abstract N2 - 1630 Objectives To characterize the effects of amphetamine on dopaminergic neurotransmission in schizophrenia.Methods Participants with schizophrenia (N=17) (5F, 12M) and [healthy participants (N=21) (8F, 13M)], aged in years, mean = 32.94 [31.33], range = (18, 48) [(18,53)], underwent two 90-min PET scans after intravenous (IV) injections of 740 Mbq (20 mCi) high-specific-activity [11C]raclopride. Five min before the first scan, they received 10 mL 0.9% NaCl intravenously (IV) (inert), and five min before the second scan, they received 0.3 mg/kg amphetamine IV (challenge). Dopamine release was calculated by means of true equilibrium bolus estimation (TREMBLE) (Wong, et al, 1998) utilizing regions of interest (ROIs) manually drawn on coregistered images of PET and MRI as follows: caudate nucleus (CN), putamen (P), and ventral striatum (VS). Dopamine release (DAR) = [BPsaline - BPamphetamine]/[BPsaline] where BP = binding potentialResults DAR in CN, P, and VS did not differentiate people with established schizophrenia (N=9) (1F, 8M) from [healthy participants (N=9) (5F, 4M)]. In contrast, a never-medicated subject suffering a first psychotic episode (a 29-year-old man, see Table) demonstrated substantial dopamine release of 0.29 CN, 0.31 P, and 0.32 VS, values far exceeding those for participants with the syndrome of Gilles de la Tourette and healthy participants (Wong, et al, 2008).Conclusions People with initial psychotic symptoms of schizophrenia without medication may exhibit marked phasic elevations of both psychotic symptoms and striatal DAR.Research Support PHS Grants RO1 MH078175, NS38927, K24 DA00412, RO1 AA12839, the Johns Hopkins Institute for Clinical and Translational Research (ICTR) Grant Number UL1 TR 001079 from the Center for Advancing Translational Sciences (NCATS), a component of NIH and NIH roadmap for Medical Research, and the Brain and Behavior Research Foundation (NARSAD) Brief Psychiatric Rating Scale scores of a 29-year-old never-medicated man with schizophrenia in minutes after intravenous injections of saline and amphetamine ER -