Abstract
Introduction: The paradoxical further damage done to ischaemic tissue when blood flow and oxygenation are restored is termed ischaemia-reperfusion injury. The underlying mechanisms are complex but centre on oxidative damage to the cell membrane, which suggest a therapeutic role for antioxidants such as endogenous amino acid taurine.
Methods: In this study, 23 rats in 5 groups were subjected to right hind limb ischaemia-reperfusion injury. The right femoral vascular bundle was exposed and the femoral vein cannulated, and a tourniquet applied to the right hind limb. The left hind limb acted as a control in each animal. In group 1 there was no treatment administered, group 2 had normal saline injected into the femoral vein distal to the tourniquet, group 3 had turbine 200mg/Kg injected distal to the tourniquet, group 4 had taurine 200mg/Kg injected proximal to the tourniquet, and group 5 had taurine 100mg/Kg distally and 100mg/Kg proximally. After 4 hours of ischaemia and 30 minutes reperfusion, gastrocnemius biopsies were taken from right and left hind limbs and their contraction strength in response to a standardised electrical impulse was measured.
Results: There was a statistically significant difference in contraction strength between right and left hind limb samples in all groups. The difference in-group 4 was an order of magnitude less than that in groups 1, 2, and 3, with an intermediate value in-group 5. Histological examination confirmed inflammatory changes consistent with ischaemia-reperfusion injury and not simple necrosis.
Conclusion: These data suggest that taurine in the reperfusing blood, rather than in the ischaemic tissues, confers some protection against ischaemia-reperfusion injury mediated functional impairment in rat skeletal muscle.
The abstracts were prepared by Raymond Moran. Correspondence should be addressed to him at the Irish Orthopaedic Assocation, c/o Cappagh National Orthopaedic Hospital, Finglas, Dublin 11, Ireland.
