Figure 1. The tissue reaction upon insertion of the microdialysis catheter was measured as interstitial concentration of prostaglandin E₂ (PGE₂) and thromboxane B₂ (TXB₂).

Four subjects were rested for 4.5 h after insertion of a microdialysis catheter just ventral to the Achilles tendon as described in the text. The interstitial concentration of PGE₂ and TXB₂ was determined in 30 min periods with the first period starting immediately after insertion of the catheter. For comparison, the time coupling between the sampling periods in this resting control study and the sampling periods in the metabolic study is indicated in the text as rest (0–90 min), exercise (Ex.; 90 to 120 min) and recovery (120–180 min).