Aims: We studied the effect of thalidomide on NF kappa B-induced TNF-alpha in acute pancreatitis-associated lung injury in the rat. Methods: Rats were intragastrically administered thalidomide (100 mg/kg) daily for 8 days and then acute pancreatitis was induced by retrograde infusion of 5% sodium taurocholate into the rat biliopancreatic duct. Serum amylase (AMY), blood oxygen partial pressure (PaO2), ratios of lung wet/dry weight, and cytoplasmic I kappa B alpha and TNF-alpha protein and nuclear NF kappa Bp65 protein were measured. Also, lung NFK kappa Bp65 and TNF-alpha mRNA were measured. Results: Compared with the model group, the pathological score of the pancreas and lung, serum AMY, ratios of lung wet/dry weight, and lung NF kappa Bp65 and TNF-alpha mRNA and protein of rats given thalidomide were decreased significantly (P<0.01), but PaO2 and I kappa B alpha protein was elevated significantly (P<0.01). Conclusion: Thalidomide may inhibit TNF-a expression via down-regulation of the NF kappa B signaling pathway to alleviate acute pancreatitis-associated lung injury in rats. (C) 2014 Elsevier GmbH. All rights reserved.