[The function of nitric oxide in the necrosis of avulsed skin flap in domestic pig].

To investigate the function of nitric oxide (NO) and nitric oxide synthetase (NOS) inhibitor, N-nitro-L-arginine methyl ester (L-NAME), the skin avulsion model was made in the lower extremity of pig. The methods of measurement of size of the survived flap, weighing, immunocytochemistry and hybridization in situ were employed, so that the survival surface area of flaps, tissue wet/dry weight ratio, NO content in the serum, gene expression of NO and NOS content in the flap tissue were determined, respectively. The results showed that the early gene expression of NOS was increased as well as the NO content and tissue wet/dry weight ratio (P < 0.01). After L-NAME was applied introvenously, the NO content and tissue wet/dry weight ratio were decreased (P < 0.01), and the survival surface area of flaps was enlarged (P < 0.01). It could be concluded that the NO might play a role in the development of the pathological changes as early congestion, edema and secondary necrosis in the avulsed skin flaps. The early application of L-NAME could do some good to the avulsed skin flap and protect it from further necrosis owing to the presence of NO.