fa تغییرات سطح سرمی نیتریک اکساید در مراحل مختلف ادم مغزی تروماتیک General پژوهشي Research Article Background and Aim: Nitric Oxide (NO) is one of the most important neurotransmitters in the brain which has a key role in brain edema and ischemia pathophysiology. The aim of this study was to determine the serum NO concentration in traumatic brain injury and its relation with Glascow Coma Scale (GCS) and consciousness level. &nbsp; Materials and Methods: In this analytic-descriptive study, patients with traumatic brain injury who had a mass volume in CT scan less than 25mm were assessed. GCS was measured during the study (14 days) and serum NO level was measured on days 0, 7 and 14 using Griess reagent method. Data were analyzed by one-way variance analysis and Pearson correlation coefficient (P < 0.05). &nbsp; Results: Results showed that there was no significant difference in serum NO concentration in different GCS scores (GCS &le; 7:7.61 &plusmn; 0.51, GCS ═ 8: 9.65 &plusmn; 1.52, GCS &ge; 9:8.5 &plusmn; 0.95 &mu; mol/lit). Also, serum NO level had no significant correlation with GCS score. Conclusion: It seems that serum NO concentration has no correlation with GCS score in traumatic brain injury. More studies on local brain NO changes in brain and CSF are needed Blood-brain barrier,Brain injuries,Edema,Nitric Oxide synthase type II,Glasgow Coma Scale 52 57 http://mcj.bums.ac.ir/browse.php?a_code=A-10-1-566&slc_lang=fa&sid=1 Mohammad Reza Ehsaei محمدرضا محمدرضا احصایی 10031947532846004352 10031947532846004352 No Associate Professor, Department of Neurosurgury, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran دانشیارگروه جراحی مغز و اعصاب و ستون فقرات، بیمارستان قائم (عج)، دانشگاه علوم پزشکی مشهد، ایران Majd Mohseni Birjandi مجد محسنی بیرجندی 10031947532846004353 10031947532846004353 No Associate Professor, Department of Neurosurgury, Ghaem Hospital, Mashhad University of Medical Sciences, Mashhad, Iran دانشیارگروه جراحی مغز و اعصاب و ستون فقرات، بیمارستان قائم (عج)، دانشگاه علوم پزشکی مشهد، ایران Seyed Mahmoud Hosseini سید محمود حسینی 10031947532846004354 10031947532846004354 No Assistant Professor, Neurosceince Research Center & Departement of Physiology, Mashahd University of Medical Sciences,Mashhad, Iran استایار مرکز تحقیقات علوم اعصاب و گروه فیزیولوژی، دانشکده پزشکی، دانشگاه علوم پزشکی مشهد، ایران Majid Khazaei مجید خزاعی 10031947532846004355 10031947532846004355 Yes Associate Professor, Department of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran. Email: khazaei@med.mui.ac.ir دانشیار گروه فیزیولوژی، دانشکده پزشکی، دانشگاه علوم پزشکی اصفهان، ایران. تلفن: 03117922407 پست الکترونیک: khazaei@med.mui.ac.ir