CONTEXT: Autism is a neurodevelopmental disorder that is characterized by repetitive and/or obsessive interests and behavior and by deficits in sociability and communication. Although its neurobiological underpinnings are postulated to lie in abnormalities of the serotoninergic and dopaminergic systems, the details remain unknown. OBJECTIVE: To determine the occurrence of changes in the binding of serotonin and dopamine transporters, which are highly selective markers for their respective neuronal systems. DESIGN: Using positron emission tomography, we measured the binding of brain serotonin and dopamine transporters in each individual with the radioligands carbon 11 ((11)C)-labeled trans-1,2,3,5,6,10-beta-hexahydro-6-[4-(methylthio)phenyl]pyrrolo-[2,1-a]isoquinoline ([(11)C](+)McN-5652) and 2beta-carbomethoxy-3-beta-(4-fluorophenyl)tropane ([(11)C]WIN-35,428), respectively. Statistical parametric mapping was used for between-subject analysis and within-subject correlation analysis with respect to clinical variables. SETTING: Participants recruited from the community. PARTICIPANTS: Twenty men (age range, 18-26 years; mean [SD] IQ, 99.3 [18.1]) with autism and 20 age- and IQ-matched control subjects. RESULTS: Serotonin transporter binding was significantly lower throughout the brain in autistic individuals compared with controls (P < .05, corrected). Specifically, the reduction in the anterior and posterior cingulate cortices was associated with the impairment of social cognition in the autistic subjects (P < .05, corrected). A significant correlation was also found between repetitive and/or obsessive behavior and interests and the reduction of serotonin transporter binding in the thalamus (P < .05, corrected). In contrast, the dopamine transporter binding was significantly higher in the orbitofrontal cortex of the autistic group (P < .05, corrected in voxelwise analysis). In the orbitofrontal cortex, the dopamine transporter binding was significantly inversely correlated with serotonin transporter binding (r = -0.61; P = .004). CONCLUSIONS: The brains of autistic individuals have abnormalities in both serotonin transporter and dopamine transporter binding. The present findings indicate that the gross abnormalities in these neurotransmitter systems may underpin the neurophysiologic mechanism of autism. Our sample was not characteristic or representative of a typical sample of adults with autism in the community.
CONTEXT: Autism is a neurodevelopmental disorder that is characterized by repetitive and/or obsessive interests and behavior and by deficits in sociability and communication. Although its neurobiological underpinnings are postulated to lie in abnormalities of the serotoninergic and dopaminergic systems, the details remain unknown. OBJECTIVE: To determine the occurrence of changes in the binding of serotonin and dopamine transporters, which are highly selective markers for their respective neuronal systems. DESIGN: Using positron emission tomography, we measured the binding of brain serotonin and dopamine transporters in each individual with the radioligands carbon 11 ((11)C)-labeled trans-1,2,3,5,6,10-beta-hexahydro-6-[4-(methylthio)phenyl]pyrrolo-[2,1-a]isoquinoline ([(11)C](+)McN-5652) and 2beta-carbomethoxy-3-beta-(4-fluorophenyl)tropane ([(11)C]WIN-35,428), respectively. Statistical parametric mapping was used for between-subject analysis and within-subject correlation analysis with respect to clinical variables. SETTING:Participants recruited from the community. PARTICIPANTS: Twenty men (age range, 18-26 years; mean [SD] IQ, 99.3 [18.1]) with autism and 20 age- and IQ-matched control subjects. RESULTS:Serotonin transporter binding was significantly lower throughout the brain in autistic individuals compared with controls (P < .05, corrected). Specifically, the reduction in the anterior and posterior cingulate cortices was associated with the impairment of social cognition in the autistic subjects (P < .05, corrected). A significant correlation was also found between repetitive and/or obsessive behavior and interests and the reduction of serotonin transporter binding in the thalamus (P < .05, corrected). In contrast, the dopamine transporter binding was significantly higher in the orbitofrontal cortex of the autistic group (P < .05, corrected in voxelwise analysis). In the orbitofrontal cortex, the dopamine transporter binding was significantly inversely correlated with serotonin transporter binding (r = -0.61; P = .004). CONCLUSIONS: The brains of autistic individuals have abnormalities in both serotonin transporter and dopamine transporter binding. The present findings indicate that the gross abnormalities in these neurotransmitter systems may underpin the neurophysiologic mechanism of autism. Our sample was not characteristic or representative of a typical sample of adults with autism in the community.
Authors: Ragy R Girgis; Mark Slifstein; Xiaoyan Xu; W Gordon Frankle; Evdokia Anagnostou; Stacey Wasserman; Lauren Pepa; Alexander Kolevzon; Anissa Abi-Dargham; Marc Laruelle; Eric Hollander Journal: Psychiatry Res Date: 2011-11-12 Impact factor: 3.222
Authors: Elizabeth Hammock; Jeremy Veenstra-VanderWeele; Zhongyu Yan; Travis M Kerr; Marianna Morris; George M Anderson; C Sue Carter; Edwin H Cook; Suma Jacob Journal: J Am Acad Child Adolesc Psychiatry Date: 2012-05-26 Impact factor: 8.829
Authors: Georgianna G Gould; Julie G Hensler; Teresa F Burke; Robert H Benno; Emmanuel S Onaivi; Lynette C Daws Journal: J Neurochem Date: 2010-12-02 Impact factor: 5.372
Authors: Logan K Wink; Martin H Plawecki; Craig A Erickson; Kimberly A Stigler; Christopher J McDougle Journal: Expert Opin Emerg Drugs Date: 2010-09 Impact factor: 4.191