Using microdialysis to investigate the local skeletal muscle inflammatory response to resistance exercise

Tissue trauma is associated with marked increases in inflammatory cytokines. Increased inflammatory cytokines have been detected in the blood after high intensity eccentric exercise and long duration aerobic exercise. The source of the increased inflammatory cytokines is not entirely clear, but increased levels of inflammatory cytokine mRNA has been detected in the skeletal muscle tissue in response to high-intensity exercise; thus implicating skeletal muscle as a potential source for the production of inflammatory cytokines in response to exercise. Microdialysis is a powerful technique that uses a small tube with a semi-permeable membrane to allow for the collection of tissue interstitial fluid sample. The purpose of this study was to determine whether an acute bout of high-intensity resistance exercise increases inflammatory cytokines in the skeletal muscle interstitium and to gain a better understanding as to the source of where the inflammatory cytokines are derived. Microdialysis probes were inserted in the vastus lateralis and blood samples were collected via venipuncture. Increases in inflammatory cytokines were detected in the interstitial fluid prior to increases in the blood; however, in general there were no differences between the trials. The results suggest that inflammatory cytokines are derived in and released from skeletal muscle.