title: Cellular and subcellular localization of cholecystokinin (CCK)-1 receptors in the pancreas, gallbladder, and stomach of mice.
abstract: Information concerning the cellular localization of cholecystokinin (CCK)-1 receptors has been discrepant and remained scanty at ultrastructural levels. The present immunohistochemical study at light and electron microscopic levels revealed the distinct localization of CCK1 receptors in visceral organs. Immunohistochemistry by use of a purified antibody against mouse CCK1 receptor was applied to fixed tissue sections of the pancreas, gallbladder, stomach, and intestine of mice. A silver-intensified immunogold method revealed the subcellular localization under electron microscope. The immunoreactivity for CCK1 receptors was selectively found in the basolateral membrane of pancreatic acinar cells and gastric chief cells but was absent in pancreatic islets and gastric D cells. Another intense expression in the gut was seen in the myenteric nerve plexus of the antro-duodenal region and some populations of c-Kit-expressing pacemaker cells in the duodenal musculature. The gallbladder contained smooth muscle fibers with an intense immunoreactivity of CCK1 receptors on cell surfaces. The restricted localization of CCK1 receptors on the basolateral membrane of pancreatic acinar cells and gastric chief cells, along with their absence in the islets of Langerhans and gastric D cells, provides definitive information concerning the regulatory mechanism by circulating CCK. Especially, the subcellular localization in the acinar cells completes the investigation for the detection of circulating CCK by the basolateral membrane.
authors.affiliation: Department of Anatomy, Hokkaido University Graduate School of Medicine, N15W7, Kita-ku, Sapporo, 060-8638, Japan.
authors.forename: Kohtarou
authors.initials: K
authors.lastname: Konno
authors.forename: Hiromi
authors.initials: H
authors.lastname: Takahashi-Iwanaga
authors.forename: Motokazu
authors.initials: M
authors.lastname: Uchigashima
authors.forename: Kyoko
authors.initials: K
authors.lastname: Miyasaka
authors.forename: Akihiro
authors.initials: A
authors.lastname: Funakoshi
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Iwanaga
mesh_terms: D000818:Animals; D005704:Gallbladder / Q000166:cytology* / Q000648:ultrastructure; D017404:In Situ Hybridization, Fluorescence; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D008854:Microscopy, Electron; D008969:Molecular Sequence Data; D010179:Pancreas / Q000166:cytology* / Q000648:ultrastructure; D043886:Receptor, Cholecystokinin A / Q000032:analysis* / Q000378:metabolism* / Q000648:ultrastructure; D013270:Stomach / Q000166:cytology* / Q000648:ultrastructure
chemical_list: D043886:Receptor, Cholecystokinin A