We attempted to investigate the abnormalities of serotonergic system in infantile autism, and
to find the relationship between the abnormalities of serotonergic system and the psychopathology
of infantile autism.
In this study, the concentrations of 5-HT in platelet rich plasma(PRP) were compared
among autistic, atypically autistic and control groups, and the psychopathology of infantile
autism, measured with Childhood Autism Rating Scale(CARS), was correlated with the
concentrations of 5-HT in PRP in autism or atypical autism group.
The subjects of this study were 48 autistic patients, 14 atypically autistic patients and 38
control children and the concentration of 5-HT was measured using HPLC-ECD(High
Performance Liquid Chromatography-Electrochemical Detection) method.
The results were as follows :
1) The concentration of PRP 5-HT in patients with atypical autism and autism was significantly
higher than that of control children, and patients with atypical autism showed the
highest level.
2) The concentration of PRP 5-HT was related with 8th CARS item, abnormal auditory
responsiveness, in autistic group. But there was no significant correlation in atypically autistic
group.
3) Age was not significantly associated with the concentration of PRP 5-HT in autistic,
atypically autistic and control groups.
4) The cognitive function(SQ) was not significantly associated with the concentration of PRP
5-HT in autistic and atypically autistic groups.
5) No significant sex difference of PRP 5-HT concentration was found in the autistic,
atypically autistic and control groups.
These results suggest that both autism and atypical autism are related with the abnormality
of serotonergic system, and the high 5-HT level is related with the symptom of abnormal
auditory responsiveness in children with infantile autism.