title: Influence of ramiprilat and losartan on ischemia reperfusion injury in rat hearts.
abstract: HYPOTHESIS/INTRODUCTION: Our aim was to investigate whether a non-hypotensive dose of ramiprilat and losartan has myocardial protective effects during myocardial ischemia/reperfusion in vivo.
  
  
  METHODS
  Three groups of rats were given 10 mg/kg per day of losartan for one (L-1W), four (L-4W) or 10 (L-10W) weeks. Another three groups were given 50 µg/kg per day of ramiprilat for one (R-1W), four (R-4W) or 10 (R-10W) weeks. The animals underwent 30 min of left anterior descending artery occlusion and subsequent reperfusion for 120 min.
  
  
  RESULTS
  Myocardial infarct size (IS) was reduced in R-1W (28.4 ± 6.3%, p < 0.001), R-4W (27.8 ± 7.4, p < 0.001), L-4W (31.8 ± 6%, p < 0.05) and L-10W (25.3 ± 5.7, p < 0.001) groups compared with a saline group (48.3 ± 7.8%). A significant reduction in the number of ventricular ectopic beats (VEBs) was noted in groups R-1W (209 ± 41, p < 0.01), R-4W (176 ± 39, p < 0.01), L-4W (215 ± 52, p < 0.05) and L-10W (191 ± 61, p < 0.01 vs. saline 329 ± 48). The incidence of irreversible ventricular fibrillation (VF) and mortality were decreased significantly only in L-10W group. There were no significant decreases in episodes of VT, the incidence of irreversible VF and mortality in all of the groups treated with ramiprilat.
  
  
  CONCLUSIONS
  These data indicate that losartan and ramiprilat protect the heart against ischemia/reperfusion injury independently of their hemodynamic effects but in a time-dependent manner.
authors.affiliation: Department of Physiology, Tarbiat Modares University, Tehran, Iran.
authors.forename: Fatemeh
authors.initials: F
authors.lastname: Safari
authors.forename: Sohrab
authors.initials: S
authors.lastname: Hajizadeh
authors.forename: Shahnaz
authors.initials: S
authors.lastname: Shekarforoush
authors.forename: Gholamreza
authors.initials: G
authors.lastname: Bayat
authors.forename: Mohsen
authors.initials: M
authors.lastname: Foadoddini
authors.forename: Ali
authors.initials: A
authors.lastname: Khoshbaten
mesh_terms: D000818:Animals; D000959:Antihypertensive Agents / Q000494:pharmacology / Q000627:therapeutic use; D001145:Arrhythmias, Cardiac / Q000150:complications / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology; D004359:Drug Therapy, Combination; D006321:Heart / Q000187:drug effects* / Q000503:physiopathology; D006339:Heart Rate / Q000187:drug effects; D053208:Kaplan-Meier Estimate; D019808:Losartan / Q000494:pharmacology* / Q000627:therapeutic use*; D008297:Male; D009203:Myocardial Infarction / Q000150:complications / Q000188:drug therapy / Q000473:pathology / Q000503:physiopathology; D015428:Myocardial Reperfusion Injury / Q000150:complications / Q000188:drug therapy* / Q000473:pathology / Q000503:physiopathology; D017257:Ramipril / Q000031:analogs & derivatives* / Q000494:pharmacology / Q000627:therapeutic use; D051381:Rats; D017208:Rats, Wistar
chemical_list: D000959:Antihypertensive Agents; C052549:ramiprilat; D019808:Losartan; D017257:Ramipril