Abstract: OBJECTIVE: To study changes in the nuclear factor-κB p65(NF-κB p65)-inducible nitric oxide synthase(i NOS)-nitric oxide(NO) signaling pathway and the effects of Xinfeng capsules(XFC) in patients with ankylosing spondylitis(AS)METHODS: One hundred twenty patients with AS were randomly divided into an XFC group and a Salazopyrin group. Sixty health subjects were included as a normal control group. In the two treatment groups, pulmonary functional parameters,forced vital capacity(FVC), forced expiratory volume in 1 second(FEV1), maximal voluntary ventilation(MVV), peak expiratory flow(PEF), forced expiratory flow at 25% of forced vital capacity(FEF25),forced expiratory flow at 50% of forced vital capacity(FEF50), and forced expiratory flow at 75% of forced vital capacity(FEF75) were determined. Enzyme linked immunosorbent assays were used for detection of the serum oxidative stress indexes,NF-κB p65, i NOS, NO, reactive oxygen species(ROS), reactive nitrogen species(RNS), malondialdehyde(MDA), superoxide dismutase(SOD), catalase(CAT), total antioxidative capacity(TAOC) and interleukin-4(IL-4), IL-10, IL-1β, and tumor necrosis factor-α(TNF-α) contents. Westergren's method was used for determination of erythrocyte sedimentation rate(ESR). High-sensitivity C-reactive protein(Hs-CRP) was detected with a 7060 full-automatic biochemical analyzer(Hitachi, Japan).RESULTS: The clinical therapeutic effect in the XFC group was significantly superior to that in the Salazopyrin group(P

Key words: Spondylitis,ankylosing, Respiratory function tests, NF-kappa B, Nitric oxide synthase, Nitric oxide, Xinfeng capsule