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Analytical Techniques for Assaying Nitric Oxide Bioactivity
Published on: June 18, 2012
Elevated plasma nitrate levels in depressive states
1Department of Neuropsychiatry, Keio University School of Medicine, 35 Shinanomachi, Shinjuku Ward, Tokyo 160-8582, Japan. e-suzuki@med.keio.ac.jp
Background:
Previous studies have shown that nitric oxide (NO) synthase inhibitors show preclinical antidepressant-like properties, suggesting that NO is involved in the pathogenesis of depression. The purpose of this study is to examine whether or not NO production increases in depressed patients.
Methods:
Plasma nitrate concentrations, an index of NO production, were measured by high-performance liquid chromatography in depressed patients (n=17) and compared with patients suffering anxiety (n=6) and with healthy controls (n=12).
Results:
Plasma nitrate concentrations were significantly higher in depressed patients than in patients with an anxiety disorder (P<0.05) or in controls (P<0.01).
Limitations:
The study group was small. The source of the surplus production of NO in patients with major depressive episode remains unclear.
Conclusions:
These results suggest that NO production is increased in depression.
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