title: Ontogeny of cholecystokinin-immunoreactive cells in the digestive tract of Atlantic halibut, Hippoglossus hippoglossus, larvae.
abstract: The appearance and distribution of cholecystokinin (CCK)-producing cells were investigated in the digestive tract of developing larvae of cultured Atlantic halibut, Hippoglossus hippoglossus. The CCK-producing cells were detected immunohistochemically, by use of a primary antiserum against CCK cloned for the Japanese flounder, Paralichthys olivaceus. No CCK-immunoreactive (IR) cells were detected in first-feeding larvae (33 days after hatching, DAH). Forty-five DAH or 12 days after first feeding, there were a few scattered CCK-IR cells in the epithelium of the anterior midgut in about 30% of the examined larvae. All larvae older than 52 DAH had CCK-IR cells in the anterior midgut, particularly frequent in the most anterior region adjacent to the pyloric caeca. No CCK-IR cells were detected in the foregut, the hindgut, or the midgut posterior to the first curvature. The CCK-IR cells spanned the intestinal epithelium from the basal lamina to the lumen and were triangular in shape, with the nucleus in the basal part and a thin apex toward the lumen. The mechanisms controlling release of bile, pancreatic enzymes, and peristalsis during the 12 days between first feeding and the first detection of CCK-IR cells remain to be clarified.
authors.affiliation: Division of Applied Biosciences, Graduate School of Agriculture, Kyoto University, Kitashirakawa, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Kamisaka
authors.forename: G K
authors.initials: GK
authors.lastname: Totland
authors.forename: M
authors.initials: M
authors.lastname: Tagawa
authors.forename: T
authors.initials: T
authors.lastname: Kurokawa
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: M
authors.initials: M
authors.lastname: Tanaka
authors.forename: I
authors.initials: I
authors.lastname: Rønnestad
mesh_terms: D000818:Animals; D002766:Cholecystokinin / Q000032:analysis* / Q000096:biosynthesis; D004064:Digestive System / Q000737:chemistry* / Q000166:cytology / Q000254:growth & development*; D005432:Flounder / Q000254:growth & development*; D007814:Larva / Q000737:chemistry* / Q000254:growth & development*; D014018:Tissue Distribution
chemical_list: D002766:Cholecystokinin