Nitric oxide synthase inhibitors improve skin flap survival in the rat

The ability of nitric oxide (NO) synthase inhibitors to reduce ischemia-induced skin flap necrosis was assessed using a modified McFarlane flap in the rat. Flap survival was significantly improved in L-NIO treated (86 +/- 2%), L-NAME-treated (84 +/- 2%), and aminoguanidine-treated (76 +/- 2%) animals compared to the saline-treated group (54 +/- 2%), P < 0.005. Inhibition of NO synthase significantly decreased the hyperemia and edema within the flaps at 24 hours post-elevation. These findings suggest that endogenous NO production contributes to ischemic necrosis and that inhibition of NO synthase may prove useful in extending survival of tissues subjected to ischemia.