Cardiovascular research institute, Isfahan University of Medical Sciences ARYA Atherosclerosis Journal 1735-3955 3 2 2010 12 08 DO L-ARGININE AND L-NAME ALTER CORONARY VASCULAR AND AORTIC ENDOTHELIAL PERMEABILITY IN NORMAL- AND HIGH-CHOLESTEROL-FED RATS? 10109 EN Majid Khazaei MD, PhD, Department of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran. Elham Haghparast MSc. Department of Physiology, Isfahan University of Medical Sciences, Isfahan, Iran. Mohammad Afshar PhD. Department of Anatomy, Birjand university of medical sciences, Birjand, Iran. Journal Article 2010 12 04 Abstract    INTRODUCTION: The objective of this study was to evaluate the effect of L-arginine (L-Arg) and L-NAME on coronary vascular and aortic endothelial permeability in normocholesterolemic (NC) and hypercholesterolemic (HC) rats.    METHODS: Forty-eight male rats were divided into NC and HC groups and each group was divided into L-Arginine-treated, L-NAME-treated and control subgroups. L-Arg (2.25%) and L-NAME (0.75 mg/ml) were dissolved in drinking water and control groups received tap water. After 8 weeks, endothelial permeability was assessed by using the Evans Blue (EB) dye method.    RESULTS: Aortic endothelial permeability was significantly higher in HC group compared to NC group (15.1±0.7 vs. 7.7±0.8 µgEB/g tissue, respectively; P<0.05). L-Arg and L-NAME treatment decreased aortic endothelial permeability in HC animals (L-Arg: 8.4±0.4 & L-NAME: 10.8±0.6 vs. 15.1±0.7 µgEB/g tissue, respectively; P<0.05). There was no significant difference in endothelial permeability in coronary circulation between HC and NC groups and L-Arg and L-NAME did not alter endothelial permeability.    CONCLUSION: It seems that L-Arg and L-NAME have different effects on endothelial permeability based on physiological and pathological conditions and type of vessel.         Keywords: L-Arginine, L-NAME, nitric oxide, endothelium, permeability. https://arya.mui.ac.ir/article_10109_f80b8c0b896704df03fb6525733de179.pdf