Send to

Choose Destination
J Neural Transm (Vienna). 2005 Apr;112(4):577-85. Epub 2004 Sep 14.

Amino acids in schizophrenia: evidence for lower tryptophan availability during treatment with atypical antipsychotics?

Author information

Vincent van Gogh Institute for Psychiatry, Venray, The Netherlands.


Amino acids play a role in neurotransmitter availability in the central nervous system, in that e.g. the synthesis of brain serotonin depends on the concentration of its precursor tryptophan. Disturbances in amino acid metabolism have been implicated in the pathophysiology of schizophrenia.In the present study the effect of a 14 week treatment with atypical antipsychotics on the plasma levels of amino acids was investigated in patients with schizophrenia and compared to normal controls.Non-responders (< or =20% decrease in BPRS at endpoint) demonstrated lower baseline values of methionine as compared to good responders (> or =50% decrease in BPRS at endpoint; p<.05) and controls (p<.01). The ratio between tryptophan and the other large neutral amino acids (Trp/LNAA ratio) in poor-responders (<40%) decreased during treatment as compared to responders (> or =40%; p<.05). It is concluded that poor or non-response to atypical antipsychotics may be associated with an impaired synthesis of serotonin in the central nervous system.

[Indexed for MEDLINE]

Supplemental Content

Full text links

Icon for Springer
Loading ...
Support Center