2017 ACVIM Forum Research Abstract Program

Our findings show that, based on antigenic expression, TGR5 is ubiquitously distributed in the gastrointestinal tract of dogs, expressed predominantly in the membrane of epithelial cells and both in the membrane and cytoplasm of ganglia, histiocytes, and enteroendocrine cells. Canine chronic enteropathy (CE) is suspected to have a multifactorial etiology, with an interplay of genetics and environmental factors and an altered gut microbiota and host immune system. Dogs with CE have alterations in the serum and fecal metabolome, including changes in fecal bile acids. Bile acids are important signaling molecules that act through the interaction with their receptors: G protein-coupled bile acid receptor 1 (TGR5) and farnesoid X receptor (FXR). TGR5 agonists have been shown to suppress TNF-a production in macrophages from the lamina propria of human patients with Crohn's disease. The aim of this study was to compare the antigenic expression of TGR5 receptors in colonic samples as well as the fecal concentration of bile acids between dogs with CE and control dogs.