Serotonergic functioning in children with oppositional defiant disorder: a sumatriptan challenge study

Background: Several studies support the notion that disturbances in the central serotonergic function are related to impulsive aggression. There is recent evidence from studies on 5-HT1B knock-out mice that this specific receptor is involved in impulsive aggressive behavior. The aim of the present study was to investigate 5-HT1B/1D receptor functioning in normal intelligent hospitalized children with oppositional defiant disorder (ODD). Methods: The growth hormone (GH) response to a challenge with the 5-HT1B/1D agonist sumatriptan was examined in 20 children with an ODD, of whom 13 had an attention-deficit/hyperactivity disorder comorbidity, and 15 normal control subjects (NC). Blood samples for growth hormone were collected repeatedly between 8:30 and 12:00 am. Sumatriptan was administered at 10 am. The effect of stress due to this procedure was assessed by measuring salivary cortisol. Results: The GH response was significantly stronger in the children with ODD. After sumatriptan injection NC children showed a significant increase in cortisol; no such pattern was present in the ODD group. Conclusions: The results suggest that the postsynaptic 5-HT1B/1D receptor is functionally more sensitive in children with ODD