COX-2 inhibitor protects rat heart against oxidative stress through a pathway independent of cyclooxygenase / 中国病理生理杂志

ABSTRACT

AIM:To investigate whether nimesulide a selective cyclooxygenase 2 (COX-2) inhibitor and piroxicam (an inhibitor of COX-1) protect the rat hearts against oxidative stress induced by hydrogen peroxide, superoxide anion or hydroxyl free radical. METHODS: Cardiac contractility, lactate dehydrogenase (LDH) and malondialdehyde (MDA) were analyzed by the Langendorff method in isolated rat hearts. Production of 6-Keto-PGF1?, a marker of COX activity, was measured in isolated rat hearts. RESULTS: Rat hearts were exposed to hydrogen peroxide (H2O2), pyrogallol (which produced superoxide anion) or Vit C+Fe2+ (which produced hydroxyl free radical) for 10 min followed by reperfusion for 30 min. H2O2 decreased cardiac contractility and increased LDH release, which was inhibited by nimesulide (3 mg/kg) LVDP 72%?10% vs 61%?11%, LDH (5.5?2.5)U/L vs (8.0?2.1)U/L, P