alpha-[11C]Methyl-L-tryptophan trapping in the orbital and ventral medial prefrontal cortex of suicide attempters

Eur Neuropsychopharmacol. 2006 Apr;16(3):220-3. doi: 10.1016/j.euroneuro.2005.09.006. Epub 2005 Nov 2.


Low serotonin neurotransmission is thought to increase vulnerability to suicidal behavior. To test this hypothesis, we measured brain regional serotonin synthesis, as indexed by PET and alpha-[(11)C]methyl-L-tryptophan trapping, in 10 patients who had made a high-lethality suicide attempt and 16 healthy controls. Compared to healthy controls, suicide attempters had reduced normalized alpha-[(11)C]methyl-L-tryptophan trapping in orbital and ventromedial prefrontal cortex. alpha-[(11)C]Methyl-L-tryptophan trapping in these regions correlated negatively with suicide intent. Low serotonin synthesis in the prefrontal cortex might lower the threshold for suicidal behavior.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Brain Mapping
  • Depressive Disorder / diagnostic imaging
  • Depressive Disorder / psychology
  • Female
  • Humans
  • Image Interpretation, Computer-Assisted
  • Male
  • Positron-Emission Tomography
  • Prefrontal Cortex / diagnostic imaging*
  • Prefrontal Cortex / metabolism*
  • Psychiatric Status Rating Scales
  • Radiopharmaceuticals* / pharmacokinetics
  • Suicide, Attempted* / psychology
  • Tryptophan / analogs & derivatives*
  • Tryptophan / pharmacokinetics


  • Radiopharmaceuticals
  • alpha-methyltryptophan
  • Tryptophan