AIM: To investigate DNA-binding activity of nuclear factor ka ppa B (NF-?B) and pyrrolidine dithiocarbamate (PDTC) anti-inflammation effect and mechanism in trinitrobenzene sulfonic acid (TNBS)-induced acute colitis in rats. METHODS: Acute colitis was induced by instilling TNBS/ ethanol into the lumen of the rat colon. Rats were randomized into PDTC-treat g roup (including group P10,P25,P50,P100), TNBS/ethanol group and normal control g roup. The rats in PDTC-treated group were injected intraperitoneally with PDTC at the dosages of 10, 25, 50, and 100 mg?kg -1 , respectively. Rats wer e killed at 4 h after enema. Colonic inflammation, the ratio of wet/dry weig ht and MPO, SOD, and MDA activity were detected. DNA-binding activity of NF-? B was assessed by EMSA. RESULTS: NF-?B activity in colon homog enate was increased markedly at acute colitis in rats. PDTC attenuates the devel opment of rat colonic inflammation but not by reducing the NF-?B activity. CONCLUSION: NF-?B is activated in rats with acute colitis, which may be a mechanism of self-protection. PDTC can attenuate the development of in flammation.