title: Effects of losartan and vanillic Acid co-administration on ischemia-reperfusion-induced oxidative stress in isolated rat heart.
abstract: BACKGROUND
  Experimental studies have demonstrated that angiotensin II (ANG-II)-induced oxidative stress contributes to the pathogenesis of I/R injury.
  
  
  OBJECTIVE
  This study was aimed to investigate the protective effects of co-administration of losartan, as a selective ANG-II type 1 receptor (AT1R) blocker, and vanillic acid (VA), as an antioxidant, in I/R-induced oxidative stress in isolated rat heart.
  
  
  METHODS
  Adult male Wistar rats were randomly divided to sham, control, and five treatment groups (n = 10). Two doses of VA (5 and 10 mg/kg), one dose of losartan (20 mg/kg) alone, and one dose of losartan in combination with either doses of VA were administered orally for 10 days. The hearts were isolated and exposed to 30 minutes ischemia and 60 minutes reperfusion, using Langendorff apparatus. I/R-induced myocardial injury was assessed by estimating the release of lactate dehydrogenase (LDH), creatine phosphokinase (CPK) and myocardial creatine kinase (CK-MB) in coronary effluent at 5, 15, and 60 minutes of reperfusion. The oxidative stress in the hearts was assessed by estimating malondialdehyde (MDA). The effects of treatments on endogenous antioxidant enzymes were assessed by measuring superoxide dismutase (SOD), glutathione peroxidase (GPx) and catalase (CAT).
  
  
  RESULTS
  There was a more significant decrease in the levels of LDH, CPK, CK-MB, and MDA as well as increase in the levels of SOD, CAT and GPx in groups that had received combined treatment in comparison to VA or losartan alone.
  
  
  CONCLUSIONS
  It may be concluded that combination of losartan with higher dose of VA decreases ischemic markers and lipid peroxidation and augments endogenous antioxidant and hence, protects myocardium against I/R-induced oxidative stress injuries.
authors.affiliation: Physiology Research Center, Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran.
authors.forename: Mahin
authors.initials: M
authors.lastname: Dianat
authors.affiliation: Physiology Research Center, Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran ; Diabetes Research Center, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran.
authors.forename: Gholam Reza
authors.initials: GR
authors.lastname: Hamzavi
authors.affiliation: Physiology Research Center, Department of Physiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Badavi
authors.affiliation: Department of Virology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, IR Iran.
authors.forename: Alireza
authors.initials: A
authors.lastname: Samarbafzadeh
keywords: Injury; Losartan; Oxidative Stress; Vanillic Acid