title: Amylin-like immunoreactivity in pancreatic X cells of the black-spotted frog Rana (Pelophylax) nigromaculata.
abstract: tIn this study, we investigated the presence of ovoid or ellipsoidal amylin-immunoreactive cells of the pancreatic islets of the black-spotted frog Rana (Pelophylax) nigromaculata. Using double immunofluorescent staining, all amylin-immunoreactive cells were shown to be immuno-negative for insulin, glucagon, and somatostatin, and they were often observed in peripheral regions of clusters of insulin-immunoreactive cells. Under immunoelectron microscopy, amylin-immunoreactive signals were detected on the secretory granules in a specific type of endocrine cells. From our results, we conclude that the amylin-immunoreactive cells correspond to X cells among the 4 distinct types of endocrine cells (B, A/PP, D, and X) previously identified in the frog. Amylin secreted from X cells may regulate the hormone secretion from A/PP cells and/or B cells through a paracrine mechanism.
authors.affiliation: Department of Biology, Fukuoka University of Education, Akamabunkyo-machi 1-1, Munakata, Fukuoka 811-4192, Japan. spiderhs@fukuoka-edu.ac.jp
authors.forename: Hirohumi
authors.initials: H
authors.lastname: Suzuki
authors.forename: Toshiharu
authors.initials: T
authors.lastname: Yamamoto
mesh_terms: D000818:Animals; D003238:Connective Tissue / Q000378:metabolism; D005934:Glucagon; D050416:Glucagon-Secreting Cells / Q000378:metabolism; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000378:metabolism; D058228:Islet Amyloid Polypeptide / Q000276:immunology / Q000378:metabolism*; D010179:Pancreas / Q000166:cytology / Q000378:metabolism*; D050418:Pancreatic Polypeptide-Secreting Cells / Q000378:metabolism; D011898:Ranidae
chemical_list: D007328:Insulin; D058228:Islet Amyloid Polypeptide; D005934:Glucagon