Fig. 7.

Arg-1 activity is increased in the serum of endotoxemic mice model. A: arginase levels in serum and in ileal mucosa of endotoxemic mice challenged with 15 mg/kg of LPS was detected at 0, 2, 6, and 15 h after injection. The data shown are representative of 3 studies that gave equivalent results. B: arginase activity in serum was measured at each time point described in A (n = 3 mice per group). C: iNOS dimerization is blocked in mucosa of endotoxemic mice. Ileal mucosa was harvested from control (0 h), 6, and 18 h LPS-stimulated (15 mg/kg) mice, and proteins were extracted and fractionated by ultrafiltration with 200-kDa MWCO membranes as described in materials and methods (representative of 3 separate experiments).