Experimental study comparing the effects of cold and warm applications on oxidative stress markers in a rat extremity ischemia-reperfusion injury model.

Background: After successful restoration of limb perfusion following limb ischemia, a series of secondary damage mechanisms, collectively known as reperfusion injury, is triggered. This study investigated the comparative effects of warming, a technique commonly used in clinical settings after extremity revascularization, and cooling, in a rat model of ischemia-reperfusion injury.

Methods: Sprague Dawley rats aged 12 to 14 weeks and weighing between 250-350 g were used. The study included four experimental groups: Sham, Control, Cold Application, and Warm Application. Ischemia was induced by occluding the femoral artery with an atraumatic vascular clamp for three hours. Cold and warm treatments were applied for two hours by immersing the hind limbs in water at specific temperatures. In the cold application group, water temperature was maintained at 12±2°C using ice cubes to lower the temperature as needed. In the warm application group, the water temperature was kept at 38±2°C by adding hot water when necessary. Twenty-four hours after the injury model was established, the animals underwent a second surgical procedure to obtain tissue samples for analyses of malondialdehyde (MDA), myeloperoxidase (MPO), poly(ADP-ribose) polymerase (PARP), catalase, and superoxide dismutase (SOD).

Results: Compared to the control group, the warm application group showed no statistically significant differences in levels of MDA (p=0.910), MPO (p=0.527), PARP (p=0.192), catalase (p=0.999), or SOD (p=0.987). In contrast, the cold application group exhibited a significant reduction in MDA, MPO, PARP, catalase, and SOD levels (p<0.001 for all).

Conclusion: To minimize reperfusion injury following limb ischemia, cold application may provide greater benefits than warming the extremity. Further studies are necessary to explore the clinical relevance and applications of this finding.