Myocardial ischaemia and reperfusion injury: reactive oxygen species and the role of neutrophil.

A growing body of evidence suggests that oxygen radicals can mediate myocardial tissue injury during ischaemia and, in particular, during reperfusion. This review focuses on the role of neutrophil as a mediator of myocardial damage. Upon reperfusion, neutrophils accumulate and produce an inflammatory response in the myocardium that is responsible, in part, for the extension of tissue injury associated with reperfusion. It has shown that the inhibition of neutrophil accumulation and adhesion is associated with decreased infarct size. This strongly suggests that myocardial cells at risk region undergo irreversible changes upon reperfusion and accumulation of neutrophils. Several pharmacological agents (ibuprofen, allopurinol, prostacyclin, and prostaglandin E analogues) protect the myocardium from reperfusion injury. In addition, the mechanisms by which these agents act and directions of research that may lead to therapeutically useful approaches are also discussed in this review.

Reliability of rodent animal models in biomedical research.

Despite the discrepancies observed between the data generated from humans and animals, it is a usual practice that the results obtained from animal models are extrapolated on humans. This review stresses that while animal models are essential for the research and development, a critical caution needs to be practiced in interpreting the results. Uncritical reliance on the results of animal experimentation can be dangerously misleading and has resulted in damages to human health in several cases. This review also discusses the role of certain confounding factors in using animal models due to which appropriate precautions need to be taken while deciding to conduct a study using animal models and caution is warranted in extrapolating the data obtained from pre-clinical studies on humans.