Background:Intestinal permeability plays an important role in the development of ulcerative colitis. Sugar molecular probes is a safe and non-invasive method to measure intestinal permeability,and its correlation with inflammatory factors and claudin-8 is not clear. Aims:To explore the correlation of sugar molecular probes with TNF-α,CRP and claudin-8 in intestinal permeability in colitis rats. Methods:Twenty-four rats were assigned randomly to model group and normal control group. Colitis model was induced by DSS solution. Expressions of TNF-α,CRP were determined by ELISA,and expression of claudin-8 was determined by immunohistochemistry. Sugar molecular probes were determined by high performance liquid chromatography. Correlations of inflammatory factors and claudin-8 with sugar molecular probes were analyzed. Results:Compared with normal control group,expressions of colonic tissue TNF-α and CRP were significantly increased while expression of claudin-8 was significantly decreased in model group(P < 0. 01);secretion of lactulose and sucrolose,ratio of lactulose/ mannitol( L/ M)were significantly increased( P < 0. 01)while mannitol secretion was significantly decreased(P < 0. 01). Secretion of lactulose and sucrolose were positively correlated with expressions of TNF-α and CRP(P < 0. 01),but negatively with expression of claudin-8(P < 0. 01). L/ M ratio and mannitol secretion were negatively correlated with expressions of TNF-α and CRP(P < 0. 01),but positively with expression of claudin-8(P <0. 01). Conclusions:Sugar molecular probes and expressions of TNF-α,CRP,claudin-8 have similar results in predicting intestinal permeability in rats. Sugar molecular probes can be used as a potential method to measure intestinal permeability.