RATIONALE: Several studies have shown that impulsive violent behavior is associated with reduced serotonin metabolism in the brain, but no data exist on possible alterations of the serotonin precursor (free L-tryptophan) levels among violent offenders. OBJECTIVES: To study free L-tryptophan and kynurenine plasma levels among antisocial violent offenders. METHODS: Free L-tryptophan and competing amino acid (CAA) plasma levels were measured among 19 male impulsive antisocial violent offenders and 19 age-matched healthy male controls. RESULTS: Mean free L-tryptophan/(CAA) plasma levels were 160% (95% CI 116%-204%) higher among offenders than controls (P=0.000). Seventeen of the 19 offenders (89.5%) had values of more than 2 SD above the mean value of controls. The levels of kynurenine, the major metabolite of tryptophan, were slightly increased in offenders. CONCLUSION: Free plasma L-tryptophan/CAA levels were markedly increased among antisocial violent offenders indicating a disturbed tryptophan metabolism.
RATIONALE: Several studies have shown that impulsive violent behavior is associated with reduced serotonin metabolism in the brain, but no data exist on possible alterations of the serotonin precursor (free L-tryptophan) levels among violent offenders. OBJECTIVES: To study free L-tryptophan and kynurenine plasma levels among antisocial violent offenders. METHODS: Free L-tryptophan and competing amino acid (CAA) plasma levels were measured among 19 male impulsive antisocial violent offenders and 19 age-matched healthy male controls. RESULTS: Mean free L-tryptophan/(CAA) plasma levels were 160% (95% CI 116%-204%) higher among offenders than controls (P=0.000). Seventeen of the 19 offenders (89.5%) had values of more than 2 SD above the mean value of controls. The levels of kynurenine, the major metabolite of tryptophan, were slightly increased in offenders. CONCLUSION: Free plasma L-tryptophan/CAA levels were markedly increased among antisocial violent offenders indicating a disturbed tryptophan metabolism.
Authors: M Elizabeth Sublette; Hanga C Galfalvy; Dietmar Fuchs; Manana Lapidus; Michael F Grunebaum; Maria A Oquendo; J John Mann; Teodor T Postolache Journal: Brain Behav Immun Date: 2011-05-14 Impact factor: 7.217
Authors: Marie Claude Ouimet; Thomas G Brown; Feng Guo; Sheila G Klauer; Bruce G Simons-Morton; Youjia Fang; Suzanne E Lee; Christina Gianoulakis; Thomas A Dingus Journal: JAMA Pediatr Date: 2014-06 Impact factor: 16.193
Authors: Päivi A Pynnönen; Erkki T Isometsä; Matti A Verkasalo; Seppo A Kähkönen; Ilkka Sipilä; Erkki Savilahti; Veikko A Aalberg Journal: BMC Psychiatry Date: 2005-03-17 Impact factor: 3.630