title: Immunocytochemical identification of polypeptide YY (PYY) cells in the human gastrointestinal tract.
abstract: Various parts of the human gastrointestinal tract were investigated immunocytochemically for the occurrence of polypeptide YY (PYY) and pancreatic polypeptide (PP). PYY-immunoreactive cells were observed in the lower part of the ileum, in the colon and in the rectum, and PP-immunoreactive cells were found in the colon and rectum. Both cell types were of the open type, i.e. they extended from the basal lamina to the gut lumen. PYY-immunoreactive cells were seen to emit cytoplasmic processes to the neighbouring goblet cells. This latter observation suggests that PYY cells may exert a paracrine action on the mucus-secreting goblet cells. Staining of consecutive thin plastic sections and staining of the same section simultaneously for two peptides showed that PYY-immunoreactivity did not occur in PP- or enteroglucagon-immunoreactive cells. On the ultrastructural level PYY-immunoreactivity was localized in basal granulated endocrine cells. These cells contained round or slightly oval electron dense granules with a mean diameter of 150 nm (range 100-300 nm).
mesh_terms: D004064:Digestive System / Q000166:cytology* / Q000648:ultrastructure; D005455:Fluorescent Antibody Technique; D005768:Gastrointestinal Hormones / Q000032:analysis*; D006651:Histocytochemistry; D006801:Humans; D007106:Immune Sera; D007124:Immunoenzyme Techniques; D008854:Microscopy, Electron; D010191:Pancreatic Polypeptide / Q000032:analysis*; D019894:Peptide YY; D010455:Peptides / Q000032:analysis*
chemical_list: D005768:Gastrointestinal Hormones; D007106:Immune Sera; D010455:Peptides; D019894:Peptide YY; D010191:Pancreatic Polypeptide