Plasma phenylethylamine in schizophrenic patients

doi:10.1016/0006-3223(91)90168-L

Biological Psychiatry

Volume 30, Issue 2, 15 July 1991, Pages 145-150

https://doi.org/10.1016/0006-3223(91)90168-L Get rights and content

Abstract

Plasma samples were collected from 41 patients who met DSM-III criteria for schizophrenia and from 34 healthy controls. Phenylethylamine (PE) levels were determined using a gas chromatography-mass spectrometry negative chemical ionization method. PE was significantly higher in the schizophrenic patients compared with controls. There were no differences in PE between paranoid and nonparanoid patients. Plasma PE did not appear to be influenced by the severity of schizophrenic symptoms (rated by BPRS, SANS, and SAPS) or by the amount of dietary phenylalanine ingested within 24 hr of testing. Plasma PE did not correlate with current or past exposure to neuroleptic medication. It was not possible, however, to test individual patients during two periods when they were taking and not taking medication. Thus it is possible that neuroleptic exposure may have confounded the results. This study provides further evidence that PE excess may play a role in the etiology of schizophrenia but does not support previous studies which suggest that such an abnormality is limited to the paranoid subgroup.

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¹: We wish to thank G. Stegeman and H. Miyashita for expert technical assistance and the Friends of Schizophrenia, Saskatchewan Health, and the Medical Research Council of Canada for financial support

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Plasma phenylethylamine in schizophrenic patients

Abstract

J Chromatogr

Progr Neuro-Psychopharmacol Biol Psychiatry

Psychiatry Res

J Psychiatr Res

Brain Res Bull

Biol Psychiatry