The 5-HT2A receptor and serotonin transporter in Asperger's Disorder: A PET study with [11C]MDL 100907 and [11C]DASB

Evidence from biochemical, imaging, and treatment studies suggest abnormalities of the serotonin system in autism spectrum disorders, in particular in frontolimbic areas of the brain. We used the radiotracers [11C]MDL 100907 and [11C]DASB to characterize the 5-HT2A receptor and serotonin transporter in Asperger's Disorder. Seventeen individuals with Asperger's Disorder (age = 34.3 ± 11.1 years) and 17 healthy controls (age = 33.0 ± 9.6 years) were scanned with [11C]MDL 100907. Of the 17 patients, eight (age = 29.7 ± 7.0 years) were also scanned with [11C]DASB, as were eight healthy controls (age = 28.7 ± 7.0 years). Patients with Asperger's Disorder and healthy control subjects were matched for age, gender, and ethnicity, and all had normal intelligence. Metabolite-corrected arterial plasma inputs were collected and data analyzed by two-tissue compartment modeling. The primary outcome measure was regional binding potential BPND. Neither regional [11C]MDL 100907 BPND nor [11C]DASB BPND was statistically different between the Asperger's and healthy subjects. This study failed to find significant alterations in binding parameters of 5-HT2A receptors and serotonin transporters in adult subjects with Asperger's Disorder.