Cellular localization of mRNAs for prostaglandin E receptor subtypes in mouse gastrointestinal tract

Regional and cellular distribution of mRNAs for prostaglandin E (PGE) receptor subtypes was investigated in the mouse gastrointestinal tract by in situ hybridization. Strong signals for EP(1) transcripts were detected in cells of the muscularis mucosae layer, especially in the body of the stomach. Intense signals for EP(3) transcripts were detected in neurons of the myenteric ganglia throughout the tract. Moderate EP(3) mRNA expression was also observed in fundic gland epithelial cells, except for surface mucous cells in the stomach. Expression of EP(4) mRNA was moderate in surface epithelial cells of the corpus and in glands from the surface to the base of the antrum. Strong EP(4) signals were observed in the epithelium in the duodenum, jejunum, and ileum. In the ileum, signals were only observed in the upper part of the villi. However, no or weak signals for EP(2) transcripts were detected. These findings suggest that PGE(2) modulates various gastric or intestinal functions via at least three different PGE receptors.