The investigation of apocynin's protective effects on skeletal muscle of experimental lower extremity ischemia-reperfusion model

Although successful results were obtained with many agents for prevention of ischemia-reperfusion (I/R) injury in experimental studies, only a small part of them were used clinically. In this study, it was aimed to investigate the influences of apocynin on tissue malondialdehyde (MDA), apoptozis and Transient Receptor Potential Melastatin 2 (TRPM2) in experimental lower extremity I/R injury. Thirty female Sprague Dawley rats aged 8-10 weeks were used in the study. Test animals were allocated to 5 groups with 6 animals in each. Infrarenal abdominal aorta clamping was done in I/R group and 2 hours ischemia and 2 hours reperfusion was applied. In apocynin-ischemia-reperfusion group (A-I/R), ischemia was created and 20 mg/kg of apocynin was administered via intravenous (iv) route 30 min before reperfusion. At the end of the test, soleus muscles were removed and the rats were decapited. TUNEL (TdT- Mediated Nick and Labeling Technique) was applied for determining apoptotic cells, avidin-biotin-peroxidase method was applied for TRPM2 immunoreactivity and mason trichrome stain was applied for histopathologic examination. Results of control and sham groups were similar. When compared with control group, while apoptozis increased together with significant histopathologic changes, TRPM2 and MDA levels decreased in I/R group. When compared with I/R group, although significant improvement was observed in histopathologic changes and apoptozis, MDA level increased, TRPM2 immunoreactivity decreased in A-I/R group. IAR group was similar with I/R group. In conclusion, it was considered that apocynin applied before I/R significantly reduced TRPM2 immunoreactivity and histopathologic changes in I/R injury and more comprehensive studies are required for its clinical use. Key words: ischemia-reperfusion injury, MDA, TRPM2, apoptozis, apocynin