Abstract:
OBJECTIVE: Skeletal muscle ischemia-reperfusion (I/R) injury is a complex process in which the inflammatory mechanisms play important role. Ischemic preconditioning (IPC) and reactive oxygen radical scavenger N-acetylcsyteine (NAC) have been shown to attenuate I/R injury. We aimed to investigate the effects of IPC and NAC on I/R induced inflammation and the influence of synchronous application.
MATERIALS and METHODS: Thirty-five Sprague-Dawley rats were randomly assigned to five groups. In sham group, infrarenal aorta was isolated without induction of ischemia. In control group, ischemia was induced for 120 min, followed by reperfusion for 50 minutes. In IPC group, three cycles of 10 min ischemia, followed by 10 min reperfusion was formed preceding I/R. NAC group rats received an intravenous NAC (20 mg/kg) at the end of ischemic period and a maintenance dose of 20mg/kg/hr throughout the reperfusion. In IPC+NAC group, an equal amount of NAC was administered in an identical time period during IPC. Blood samples were obtained at the end of reperfusion for analysis of IL-1β, IL-6 and TNF-α level then rats were sacrificed.
RESULTS: All serum cytokine levels which were analyzed in this study were found to be significantly increased in control group in comparison with sham group. Although cytokine levels in the study groups were moderately increased as compared with sham group, all of three groups had significantly reduced levels than control group. There were no significant differences between the study groups regarding the serum cytokine levels.
CONCLUSION: These findings indicate that inflammation plays an essential role in skeletal muscle I/R injury. Our results suggested IPC and NAC exert beneficial effects on I/R induced inflammatory process in skeletal muscle. It was observed that there was no superiority of either of the measures over each other regarding the serum cytokine levels and concomitant use of them did not generate an additional benefit.
