In both DSS- and TNBS-induced mouse models, 5-HT4 activation reduced inflammation in colons of mice with colitis, and, in noninflamed colons of wild-type mice, the inhibition of 5-HT4 resulted in decreased epithelial proliferation and barrier dysfunction and increased bacterial translocation to the liver and spleen, with signs of colitis within 3 days after the administration of 5-HT4 inhibitors [160]. This evidence concerns the gene HTR4 and colitis.