RESUMO
BACKGROUND: Heparin and heparin derivatives with low anticoagulant activity exhibit a wide spectrum of biological functions affecting adhesion, activation and trafficking of leukocytes. METHODS: We investigated the in vitro effect of heparin and a low molecular weight heparin derivative (LMWH) on nitric oxide (NO) production by human polymorphonuclear leukocytes (PMN). RESULTS: N-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated NO production was significantly decreased by heparin at doses of 0.5 and 5 micrograms/mL, while LMWH was only effective at doses of 50 and 200 micrograms/mL by means of a mechanism not related to NO synthase (NOS) activity. CONCLUSIONS: These results support the hypothesis that heparin and LMWH derivatives may offer therapeutic benefit for inflammatory diseases where NO plays a protagonic role.
