Open AccessIs postconditioning effective in prevention against long-lasting myocardial ischemia in the rabbit?
Author(s) -
Robert Létienne,
Yannick Calmettes,
Bruno Le Grand
Publication year - 2009
Publication title -
physiological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.647
H-Index - 70
eISSN - 1802-9973
pISSN - 0862-8408
DOI - 10.33549/physiolres.931596
Subject(s) - coronary occlusion , cardioprotection , medicine , occlusion , cardiology , myocardial infarction , ischemia , ischemic preconditioning , anesthesia
The goal of the study was to determine whether postconditioningprotects against different ischemia durations in the rabbit.Rabbits were assigned to a 20-, 25-, 45- or 60-min coronaryocclusion followed by 24-h of reperfusion. Rabbits received nofurther intervention (control) or were postconditioned with fourcycles of 30-s occlusion and 30-s reperfusion after myocardialinfarction. Plasma levels of troponin I were quantified throughoutreperfusion. In control conditions, infarct sizes (% area at riskusing triphenyltetrazolium chloride) after 20, 25, 45 and 60 minof coronary occlusions were 23±3, 51±4, 70±3 and 81±3 %,respectively. With 20 and 25 min occlusion, postconditioningreduced infarct size by 43±10 and 73±21 %, respectively. On theother hand, with 45 or 60 min occlusion, postconditioning had nosignificant effects on infarct size (61±3 and 80±2 % of area atrisk). Preconditioning protocol was performed with 25- and60-min coronary occlusion. As expected, preconditioningsignificantly reduced infarct size. In conclusion, in the rabbit, thecardioprotection afforded by postconditioning is limited to lessthan 45 min coronary occlusion.