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has been cited by the following article:

• TITLE: Exorphins in urine from schizoaffective psychotics

  AUTHORS: Dag Tveiten, Karl L. Reichelt

  KEYWORDS: Exorphins; Schizoaffective; Peptide; Mass-Spectrometry

  JOURNAL NAME: Open Journal of Psychiatry, Vol.2 No.3, July 25, 2012

  ABSTRACT: Hyperpeptiduria and opioid excess have been reported in schizophrenia. According to Prof. Dr. L. Lindstrom, Sweden opioids may explain the patho-physiology of this syndrome. Therefore it is critical to elucidate the presence and nature of opioids in schizophrenia and diagnostic sub groups. First morning urine from untreated schizoaffective patients (ICD-10: F 25.1) was separated on HPLC and peaks that elute where different opioid standards appear, freeze dried, re-dissolved in methanol/water (50/50) and 10mM formic acid. Mass spectrometry and MS/MS or fragmentation mass spectrometry was performed. We found fragmentation pattern of beta-casomorphin 1-3 and 1-4 (bovine) identical to synthetic standards from Bachem. The aggregation tendency of peptides was much in evidence. The reported exorphins were found in the urine from 8 of 12 untreated schizoaffective patients.