title: Faulty serotonin--DHEA interactions in autism: results of the 5-hydroxytryptophan challenge test.
abstract: BACKGROUND
  Autism is accompanied by peripheral and central disorders in the metabolism of serotonin (5-HT). The present study examines plasma dehydroepiandrosterone-sulphate (DHEA-S) and the cortisol/DHEA-S ratio following administration of L-5-hydroxytryptophan (5-HTP), the direct precursor of 5-HT, to autistic patients.
  
  
  METHODS
  Plasma DHEA-S levels were determined both before and after administration of 5-HTP or placebo, on two consecutive days in a single blind order in 18 male autistic patients and 22 matched healthy controls.
  
  
  RESULTS
  The 5-HTP-induced DHEA-S responses were significantly higher in autistic patients than in controls. In baseline conditions, the cortisol/DHEA-S ratio was significantly higher in autistic patients than in controls.
  
  
  CONCLUSIONS
  The results suggest that autism is accompanied by a major disequilibrium in the serotonergic system. The increased Cortisol (neurotoxic) versus DHEA-S (neuroprotective) ratio suggests that an increased neurotoxic potential occurs in autism.
  
  
  CONCLUSIONS
  It is concluded that a disequilibrium in the peripheral and central turnover of serotonin and an increased neurotoxic capacity by glucocorticoids are important pathways in autism.
authors.affiliation: University Center of Child and Adolescent Psychiatry, A.Z. Middelheim, Faculty of Medicine, University of Antwerp, Wilrijk, Belgium. jan.croonenberghs@zna.be
authors.forename: Jan
authors.initials: J
authors.lastname: Croonenberghs
authors.forename: Kristien
authors.initials: K
authors.lastname: Spaas
authors.forename: Annick
authors.initials: A
authors.lastname: Wauters
authors.forename: Robert
authors.initials: R
authors.lastname: Verkerk
authors.forename: Simon
authors.initials: S
authors.lastname: Scharpe
authors.forename: Dirk
authors.initials: D
authors.lastname: Deboutte
authors.forename: Michael
authors.initials: M
authors.lastname: Maes
mesh_terms: D006916:5-Hydroxytryptophan; D000293:Adolescent; D000704:Analysis of Variance; D001321:Autistic Disorder / Q000097:blood* / Q000175:diagnosis*; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood*; D006801:Humans; D006854:Hydrocortisone / Q000097:blood; D008297:Male; D011569:Psychiatric Status Rating Scales; D012701:Serotonin / Q000097:blood*; D016037:Single-Blind Method
chemical_list: D012701:Serotonin; D019314:Dehydroepiandrosterone Sulfate; D006916:5-Hydroxytryptophan; D006854:Hydrocortisone