Objective To investigate the changes and significance of intercellular adhesion molecule-1 (ICAM-1) and tumor necrosis factor-α (TNF-α) in intestinal mucosa in rats with obstructive jaundice. MethodsTwenty-four SD rats were randomly divided into sham operation (SO) group and bile duct ligation (BDL) group, and each group were randomly divided into the day 7 and day 14 subgroup. The expression of ICAM-1 was assayed by immunohistochemistry. The level of TNF-α was determined by ELISA. The activity of myeloperoxidase (MPO) and diamine oxidase (DAO) was determined as well.ResultsOn the day 7 and 14, in the bile duct ligation group, the ICAM-1 protein was mainly expressed in the intestinal epithelia and increased with the time on (P<0.05); the level of TNFα increased from (14.25±1.01) ng/g to (23.83±1.43) ng/g (P<0.01); the intestinal DAO activity decreased from (1.70±0.36) U/mg to (1.22±0.41) U/mg (P<0.01),and plasma DAO activity increased from (6.44±1.74)U/ml to (8.93±1.29) U/ml (P<0.01); the MPO activity increased from (2.85±1.22 ) U/mg to (4.93±1.37) U/mg (P<0.01). ConclusionThe ICAM-1 expression is significantly upregulated and the level of TNFα significantly increases after bile duct ligation, which may be involved in the PMNmediated injury to intestinal mucosa.