title: Evidence for the colocalization of gastrin/CCK- and PYY/PP-immunoreactive substances in the small intestine of the lizard Podarcis hispanica: immunocytochemical and ultrastructural study.
abstract: Peptide tyrosine tyrosine/pancreatic polypeptide (PYY/PP)- and C-terminal gastrin/cholecystokinin (G/CCK)-immunoreactive cells were investigated in the intestine of the lizard Podarcis hispanica, using immunocytochemistry with light and electron microscopy. Immunolabeling of consecutive semithin sections revealed coexistence of PYY/PP- and C-terminal G/CCK-like substances in some cells, while in others only PYY/PP or G/CCK immunoreactivity was found. Appropriate absorption controls excluded cross-reactivity between the antisera used. Ultrastructurally G/CCK+, PYY/PP+ cells were similar to G/CCK+, PYY/PP- cells but different from PYY/PP+, G/CCK- cells. Although virtually nothing is known concerning the physiological effects of these peptides in reptiles, their colocalization in the same cells in the intestine of Podarcis hispanica suggests a close relationship between them in the regulation of the digestive process.
authors.affiliation: Department of Histology and Pathology, University of Navarra, Pamplona, Spain.
authors.forename: M A
authors.initials: MA
authors.lastname: Burrell
authors.forename: A C
authors.initials: AC
authors.lastname: Villaro
authors.forename: P
authors.initials: P
authors.lastname: Sesma
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002766:Cholecystokinin / Q000378:metabolism*; D003429:Cross Reactions; D004151:Dipeptides / Q000378:metabolism; D005755:Gastrins / Q000378:metabolism*; D007150:Immunohistochemistry; D007421:Intestine, Small / Q000276:immunology / Q000378:metabolism* / Q000648:ultrastructure; D008116:Lizards / Q000378:metabolism*; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D010191:Pancreatic Polypeptide / Q000276:immunology / Q000378:metabolism*
chemical_list: D004151:Dipeptides; D005755:Gastrins; C042696:tyrosyltyrosine; D010191:Pancreatic Polypeptide; D002766:Cholecystokinin