عنوان مقاله [English]
نویسنده [English]چکیده [English]
The hydroxy-carboxylic acid receptor 2 (HCA2 receptor) is the target of niacin. In the present study we describe the expression pattern of these receptors in cells of different parts of alimentary canal (from esophagus to rectum) of rats by immunohistochemical method. Six adult male Wistar rats were euthanized under deep anesthesia. Five μm-paraffin transverse sections were made from esophagus, stomach duodenum, jejunum, ileum, cecum, colons and rectum. The primary antibody for immunohistochemical staining was rabbit polyclonal GPR109A antibody (1:300, incubation for one night at 4°C) which reacts with rat HCA2 receptor. Secondary antibody was HRP-conjugated. We observed weak immunoreactivity in epithelial cells of esophagus and non-glandular stomach, strong immunoreactivity of HCA2 receptors in epithelial cells of duodenum, jejunum, ileum and jejunal muscular layer. Moreover, colon showed weak and rectum showed no immunoreactivity. Immunoreactivity was strong in base of caecum. In conclusion, HCA2 receptor proteins are abundantly present in intestinal epithelium and base of caecum of rats which make them a proper laboratory animal for future studies on these receptors in gastrointestinal tract.