PURPOSE: to study oxidative stress (MDA) and total antioxidant status (CAT) in fragments of randomic ischemic skin flaps from rat dorsum. METHODS: 18 male rats, young adults (Wistar EPM-1, 290 - 350g), that underwent elevation of randomic ischemic flaps from dorsum, were divided in three groups (N=6), according to post-operative time-points: immediate (POI), third and seventh post-operative days (PO3 and PO7), respectively. At the end, peripheral blood samples and tissue fragments of the flap and of normal skin outside flap were draw for MDA and CAT measurement. RESULTS: serum MDA values in group POI were significantly lower than those in PO3 and PO7, both latter in the same range. No differences were found among MDA values of the skin samples in any of the three groups. The analysis of the total antioxidant status of the animal’s serum (CAT) did not show significant differences among the three groups. However, in the skin flap samples, the CAT values significantly decreased with time. CONCLUSION: The lack of significant differences among MDA values in skin samples from all groups, and the decreasing CAT values with time, suggest that the existence of necrosis at the distal portion of flaps in group PO7 is due not only to oxidant aggression but mainly to the reduction of local antioxidant status.
Skin flaps; Free radicals; Antioxidants; Rats
