title: Immunohistochemical analysis of cholecystokinin A receptor distribution in the rat pancreas.
abstract: Cholecystokinin (CCK) plays a major role in the regulation of pancreatic enzyme secretion based on its binding to the CCK-A receptor (CCK-AR). While CCK-AR is known to be expressed in rat islet B cells, the localization of CCK-AR in rat pancreatic A and D cells remains poorly understood. The aim of this study was to identify the localization of CCK-AR in rat pancreatic islets by means of double immunofluorescence straining with antibodies against CCK-AR, glucagon, insulin and somatostatin and with in situ hybridization to detect its transcript. CCK-AR-like immunoreactive cells were found to overlap both with glucagon-like immunoreactive cells and insulin-like immunoreactive cells but not with somatostatin-like immunoreactive cells. An in situ hybridization study using a cRNA probe for CCK-AR revealed that CCK-AR mRNA was expressed in the center and periphery of the pancreatic islets. Further to this, immunofluorecsence staining using anti-glucagon antibody was carried out after in situ hybridization using the CCK-AR cRNA probe in order to identify CCK-AR mRNA expressing cells. CCK-AR mRNA exhibited a distribution pattern almost identical to that of glucagon-like immunoreactive cells. These results show clearly that CCK-AR exists not only in B but also in A cells of the rat pancreas, suggesting that CCK regulates the secretion of insulin and glucagon at least partly via CCK-AR.
authors.affiliation: Department of Anatomy, Showa University School of Medicine, 1-5-8 Hatanodai Shinagawa-ku, Tokyo 142-8555, Japan.
authors.forename: Haruaki
authors.initials: H
authors.lastname: Kageyama
authors.forename: Tetsuro
authors.initials: T
authors.lastname: Kita
authors.forename: Shigeru
authors.initials: S
authors.lastname: Horie
authors.forename: Fumiko
authors.initials: F
authors.lastname: Takenoya
authors.forename: Hisayuki
authors.initials: H
authors.lastname: Funahashi
authors.forename: Sachi
authors.initials: S
authors.lastname: Kato
authors.forename: Masami
authors.initials: M
authors.lastname: Hirayama
authors.forename: Eun
authors.initials: E
authors.lastname: Young Lee
authors.forename: Junko
authors.initials: J
authors.lastname: Sakurai
authors.forename: Shuji
authors.initials: S
authors.lastname: Inoue
authors.forename: Seiji
authors.initials: S
authors.lastname: Shioda
mesh_terms: D000818:Animals; D002766:Cholecystokinin / Q000378:metabolism; D005934:Glucagon / Q000378:metabolism; D007150:Immunohistochemistry; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000166:cytology / Q000502:physiology*; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D043886:Receptor, Cholecystokinin A / Q000096:biosynthesis*
chemical_list: D007328:Insulin; D043886:Receptor, Cholecystokinin A; D005934:Glucagon; D002766:Cholecystokinin