Is the Arginine-Nitric Oxide Pathway Involved in the Pathogenesis of Schizophrenia?

Department of Psychiatry, Gaziantep University, Ayıntap, Gaziantep, Turkey
Neuropsychobiology (Impact Factor: 2.26). 02/2003; 47(2):61-5. DOI: 10.1159/000070010
Source: PubMed


The reciprocal regulation of arginase and nitric oxide synthase (NOS) in L-arginine-metabolizing pathways has been demonstrated. There are various evidences of the role of the nitric oxide (NO) in several neuropsychiatric disorders including schizophrenia. However, there is no study which has investigated the role of arginase as an important part of the arginine regulatory system affecting NOS activity in schizophrenia. This study aims to investigate arginase, manganese (Mn) and total nitrite levels (a metabolite of NO) and their relationship to the arginine-NO pathway in patients with schizophrenia. Arginase activities, Mn and total nitrite levels were measured in plasma from 46 patients with schizophrenia and 32 healthy control subjects. Plasma arginase activities and Mn were found to be significantly lower and total nitrite level higher in patients with schizophrenia compared with controls. Our results suggest that the arginine-NO pathway is involved in the pathogenesis of schizophrenia.

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Available from: Hasan Herken, Apr 21, 2014
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    • "Schizophrenia is a chronic and severe psychiatric disease that affects about 1% of the population and causes disability[1,2]. There are genetic and biochemical studies focused on the etiopathogenesis of schizophrenia[3]. Current diagnostic approaches for schizophrenia are based on patient interviews, which entail a subjective assessment of clinical symptoms. "
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    • "They include such elements as copper (Cu), manganese (Mn), selenium (Se), zinc (Zn), and iron (Fe). The idea that abnormal levels of these elements are related to schizophrenia is not recent (Blaustein and Ickowicz, 1983; Gould et al., 1983; Yanik et al., 2003; Grabrucker et al., 2011). However, this hypothesis has been raised based on studies done in non-neural tissues (blood, hair, and liquor) or postmortem neural tissues, which may not be a bona fide representation of what occurs in the brain of schizophrenic patients. "
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    • "Human genetic research has identified schizophrenia risk genes encoding neuronal NOS (Shinkai et al., 2002; Reif et al., 2006; Cui et al., 2010). Furthermore, plasma arginase activity has been found to be decreased in schizophrenic patients (Yanik et al., 2003), and the serum levels of L-ornithine positively correlate with the disease duration (Tomiya et al., 2007). Agmatine and polyamines putrescine, spermidine and spermine have also been suggested to play a role in the aetiology and pathology of schizophrenia (Fiori and Turecki, 2008). "
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