title: Altered diurnal variation of nitric oxide production in patients with panic disorder.
abstract: The aim of this prospective study was to investigate the diurnal change in serum nitric oxide (NO) levels in active and remission phases of patients with panic disorder. This study included 15 patients fulfilling the criteria for panic disorder of Diagnostic and Statistical Manual of Mental Disorders--Fourth Edition and 15 healthy controls matched for age and sex. All patients were receiving a selective serotonin reuptake inhibitor at therapeutic doses. The serum nitrite and nitrate levels of subjects were determined at 10:00 a.m. after overnight fasting and at 3:00 p.m. 2 hours after lunch. NO levels of all patients measured in the morning were significantly higher than those of controls. The patients were also divided into active and remission groups according to clinical status and Panic Agoraphobia Scale's cut-off point. There were no statistically significant differences in serum nitrite and nitrate levels of the active group between the 10:00 a.m. and 3:00 p.m. measurements. In contrast, statistically significant differences were found in the serum levels of nitrite (p<0.05) and nitrate (p<0.05) in the remission group. Notably, the afternoon nitrite and nitrate levels of the remission group were higher than those of the morning levels as seen in control subjects. Thus, diurnal variation of NO production is altered in patients with panic disorder but is resumed in the remission phase. The present study suggests that serum NO levels are a good marker for evaluation of panic disorder.
authors.affiliation: Department of Psychiatry, Inonu University Medical School, Malatya, Turkey.
authors.forename: Burhanettin
authors.initials: B
authors.lastname: Kaya
authors.forename: Süheyla
authors.initials: S
authors.lastname: Unal
authors.forename: Aysun Bay
authors.initials: AB
authors.lastname: Karabulut
authors.forename: Yusuf
authors.initials: Y
authors.lastname: Türköz
mesh_terms: D000379:Agoraphobia; D001007:Anxiety; D002940:Circadian Rhythm; D006801:Humans; D009566:Nitrates / Q000097:blood; D009569:Nitric Oxide / Q000096:biosynthesis*; D019001:Nitric Oxide Synthase / Q000235:genetics; D052247:Nitric Oxide Synthase Type II; D009573:Nitrites / Q000097:blood; D016584:Panic Disorder / Q000503:physiopathology*; D011446:Prospective Studies; D012016:Reference Values
chemical_list: D009566:Nitrates; D009573:Nitrites; D009569:Nitric Oxide; C496319:NOS2 protein, human; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II