Further Evidence of Dopamine Transporter Dysregulation in ADHD: A Controlled PET Imaging Study Using Altropane

doi:10.1016/j.biopsych.2006.12.008

Biological Psychiatry

Volume 62, Issue 9, 1 November 2007, Pages 1059-1061

https://doi.org/10.1016/j.biopsych.2006.12.008 Get rights and content

Background

The dopamine transporter (DAT) is known to be a key regulator of dopamine, and recent studies of genetics, treatment, and imaging have highlighted the role of DAT in attention-deficit/hyperactivity disorder (ADHD). The findings of in vivo neuroimaging of DAT in ADHD have been somewhat discrepant, however.

Method

Dopamine transporter binding was measured using a highly selective ligand (C-11 altropane) and positron emission tomography (PET). The sample consisted of 47 well-characterized, treatment-naïve, nonsmoking, non-comorbid adults with and without ADHD. Additionally, control subjects had few symptoms of ADHD.

Results

Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without this disorder.

Conclusions

These results confirm abnormal DAT binding in the striatum of adults with ADHD and provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD.

Section snippets

Subjects

Subjects consisted of 47 volunteers between 18 and 55 years of age. The subjects with ADHD had to satisfy full diagnostic criteria for DSM-IV ADHD (Biederman et al. 1993). Control subjects could have at most two mild symptoms of ADHD and no family history of ADHD. We excluded potential subjects if they had clinically significant chronic medical conditions, abnormal baseline laboratory values, IQ <80, Axis I psychiatric conditions, drug or alcohol abuse or dependence, previous exposure to

Results

Although subjects with and without ADHD had similar sociodemographic characteristics, ADHD subjects were somewhat older than the control subjects (p < .01) (Table 1). Thus, subsequent analyses are corrected for age.

In multivariate analyses including both diagnoses and age, DAT binding was statistically significantly different between diagnostic groups only in the right caudate (t = 2,77, df = 45, p = .008). Before age correction, right caudate DAT binding was not statistically different (3.2 ±

Discussion

This study used a highly selective radioactive ligand (¹¹C-altropane) and PET to examine DAT binding in the striatum in a large sample of well-characterized adults with and without ADHD. Results showed significantly increased DAT binding in the right caudate in adults with ADHD compared with matched control subjects without the disorder. These results provide further support that dysregulation of DAT may be an important component of the pathophysiology of ADHD.

This study has some noteworthy

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Brief ReportFurther Evidence of Dopamine Transporter Dysregulation in ADHD: A Controlled PET Imaging Study Using Altropane

Background

Method

Results

Conclusions

Section snippets

Subjects

Results

Discussion

Biol Psychiatry

Biol Psychiatry

Neurosci Biobehav Rev

Behav Brain Res

Biol Psychiatry

Am J Geriatr Psychiatry

The behavioural and motor consequences of focal lesions of the basal ganglia in man

Brain

Patterns of psychiatric comorbidity, cognition, and psychosocial functioning in adults with attention deficit hyperactivity disorder

Am J Psychiatry

Brief Report
Further Evidence of Dopamine Transporter Dysregulation in ADHD: A Controlled PET Imaging Study Using Altropane