Cortical Serotonin 5-HT 2A Receptor Binding and Social Communication in Adults With Asperger’s Syndrome: An in Vivo SPECT Study

VU University Amsterdam, Amsterdamo, North Holland, Netherlands
American Journal of Psychiatry (Impact Factor: 12.3). 06/2006; 163(5):934-6. DOI: 10.1176/appi.ajp.163.5.934
Source: PubMed


The cause of autistic spectrum disorder (i.e., autism and Asperger's syndrome) is unknown. The serotonergic (5-HT) system may be especially implicated. However, cortical 5-HT2A receptor density in adults with the disorder has not been examined, to the authors' knowledge.
The authors investigated cortical 5-HT2A receptor binding in eight adults with Asperger's syndrome and in 10 healthy comparison subjects with single photon emission computed tomography and the selective 5-HT2A receptor ligand 123I iodinated 4-amino-N-[1-[3-(4-fluorophenoxy)propyl]-4-methyl-4-piperidinyl]-5-iodo-2-methoxybenzamide (123I-5-I-R91150).
People with Asperger's syndrome had a significant reduction in cortical 5-HT2A receptor binding in the total, anterior, and posterior cingulate; bilaterally in the frontal and superior temporal lobes; and in the left parietal lobe. Also, reduced receptor binding was significantly related to abnormal social communication.
The authors' findings suggest that adults with Asperger's syndrome have abnormalities in cortical 5-HT2A receptor density and that this deficit may underlie some clinical symptoms.

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    • "Alterations in brain 5-HT receptor density were found in autistic patients. A reduction of 5-HT2A binding sites in the cingulate, frontal, and temporal cortex was detected in adults with Asperger syndrome by single photon emission computed tomography (SPECT; Murphy et al., 2006), although a later PET study found contrasting results (Girgis et al., 2011). A reduced density of 5-HT1A and 5-HT2 receptors in posterior cingulate cortex and fusiform cortex, brain regions involved in social and emotional behaviors, was observed in post-mortem brain tissue from young adults diagnosed with autism other than Asperger syndrome (Oblak et al., 2013). "
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