The Antioxidant Effect of Melatonin on Myocardial Ischemia Reperfusion Injury in Experimental Studies

A lot of mechanisms play major role in the myocardial ischemia reperfusion injury (MI/R), especially reactive oxygen species (ROS) which they formed rapidly when molecular oxygen enters into the cell. Melatonin, major hormone of the pineal gland, has very strong antioxidant and free radical scavenger effects. Besides, melatonin plays an important role in the regulation of various body functions including circadien sleep rhythms, blood pressure, oncogenesis, retinal function, and immunity. It can be possible to say that oxidative stress occurs during MI/R and melatonin administration exerts an infarct size limiting effect, antiapoptic, antiarryhtmic effects and enhances antioxidant activity of the heart. Key words: Myocardial ischemia-reperfusion, free radicals, no-reflow, necrosis, antioxidants