In this study we found the expression of TLR4 mRNA and protein was elevated in ileum of ANP mice, anti-HMGB1 antibody treatment reduced TLR4 expression, suggesting TLR4 may be the downstream signaling molecule of HMGB1 involved in the intestinal barrier dysfunction in AP, but the definite role of TLR4 in intestinal barrier dysfunction in AP is await to further research. Here, HMGB1 is linked to alkaline phosphatase measurement.