Cyclooxygenase-2 plays an essential part in cardioprotection of delayed phase of recombinant human erythropoietin preconditioning in rats.
OBJECTIVE
To study the cardioprotection of recombinant human erythropoietin (rhEPO) preconditioning (EPC) and to investigate the role and possible mechanism of cyclooxygenase (COX)-2 in the delayed phase of EPC.


METHODS
In phase 1, myocardial ischaemia reperfusion (I-R) rat model was established by 30 minutes ligation of left descending coronary and three hours of reperfusion. Rats were given 0.9% saline solution or rhEPO 24 hours before I-R protocol. COX-2 selective inhibitor celecoxib was given for further investigation of the cardioprotection of EPC. At the end of I-R protocol, infarct sizes were measured and ultrastructural organisations were studied. In phase 2, myocardial COX-2 mRNA expressions and prostaglandins (PGs) contents were studied in different groups after euthanasia.


RESULTS
It was found that EPC could elicit potent cardioprotection against I-R injury, shown by reduction of infarct size and improvement of ultrastructural organisation; whereas administration of celecoxib resulted in complete loss of this protection. EPC resulted in robust increase in COX-2 mRNA and PGs levels that were also abrogated by celecoxib.


CONCLUSIONS
COX-2 plays an essential part in cardioprotection of the delayed phase of EPC in rats, which might be related to actions of PGE(2) or PGI(2), or both.
Liu
X
X
Department of Anaesthesiology, Jinling Hospital, Nanjing, China.
Zhou
Z
Z
Feng
X
X
Jia
Z
Z
Jin
Y
Y
Xu
J
J
D000818:Animals; D000068579:Celecoxib; D051546:Cyclooxygenase 2 / Q000502:physiology*; D052246:Cyclooxygenase 2 Inhibitors / Q000627:therapeutic use; D004921:Erythropoietin / Q000627:therapeutic use*; D019157:Ischemic Preconditioning, Myocardial; D008026:Ligation; D008297:Male; D017202:Myocardial Ischemia / Q000628:therapy*; D015428:Myocardial Reperfusion Injury / Q000517:prevention & control*; D011720:Pyrazoles / Q000627:therapeutic use; D051381:Rats; D017207:Rats, Sprague-Dawley; D011994:Recombinant Proteins; D013449:Sulfonamides / Q000627:therapeutic use
D052246:Cyclooxygenase 2 Inhibitors; D011720:Pyrazoles; D011994:Recombinant Proteins; D013449:Sulfonamides; D004921:Erythropoietin; D051546:Cyclooxygenase 2; D000068579:Celecoxib