Apoptotic cell death makes a minor contribution to reperfusion injury in skeletal muscle in the rat

Objective: to determine if apoptotic cell death contributes to skeletal muscle reperfusion injury. Methods: leg ischaemia was induced in rats with a tourniquet and maintained for 4 h before reperfusion for 24 or 72 h. Apoptosis was assessed by morphology, in situ end labelling of DNA fragments, DNA laddering, expression of p53 mRNA and detection of caspase-3-like proteolytic activity. Results: increased caspase-3-like activity was detected in muscle following ischaemia and zero, 24 h or 72 h of reperfusion. Levels remained relatively low but with a highly significant difference in enzyme activity between the ischaemic and non-ischaemic legs (p