The 5-HT _2A 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-HT _2A receptor and serotonin transporter in Asperger's Disorder. Seventeen individuals with Asperger's Disorder (age=34.3±11.1years) and 17 healthy controls (age=33.0±9.6years) were scanned with [ ¹¹C]MDL 100907. Of the 17 patients, eight (age=29.7±7.0years) were also scanned with [ ¹¹C]DASB, as were eight healthy controls (age=28.7±7.0years). 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 BP _ND. Neither regional [ ¹¹C]MDL 100907 BP _ND nor [ ¹¹C]DASB BP _ND was statistically different between the Asperger's and healthy subjects. This study failed to find significant alterations in binding parameters of 5-HT _2A receptors and serotonin transporters in adult subjects with Asperger's Disorder.