Changes in the expression of galanin and galanin receptors in the wall of the colon in pigs experimentally infected with Brachyspira hyodysenteriae

The expression of galanin (GAL) and its three receptors (GalR1, GalR2, and GalR3) were studied with real-time PCR in the colonic wall of pigs suffering from experimental colitis caused by the infection with Brachyspira hyodysenteriae. The expression was studied in the muscular membrane, mucosa/submucosa layer, and in lymphocytes isolated from mucosa/submucosa. The expression levels were normalized to glyceraldehyde-6-phosphate dehydrogenase (GAPDH) expression and compared to expression levels in control animals. GAL expression was found in all three studied compartments of the colonic wall. A significant decrease in GAL expression level was found in the mucosa/submucosa and in isolated lymphocytes, whereas the decrease was much less profound in the muscular membrane. In the case of galanin receptors their expression was found in all studied compartments of the colonic wall, however at different levels, as compared to GAPDH expression. The decrease of galanin receptors expression was found in all studied compartments of the colonic wall of the sick animals.