title: Characterization and species differences in gastric ghrelin cells from mice, rats and hamsters.
abstract: Ghrelin is a newly identified gastric peptide hormone that has various important functions, including growth-hormone release and appetite stimulation. Ghrelin-immunoreactive cells (ghrelin cells) are characterized by X-type endocrine cells in the rat stomach. In the present study, we analysed ghrelin cells in fundi of stomach from ICR mice and Syrian hamsters immunohistochemically, immunoelectron microscopically and morphometrically, and compared the results with those from Wistar rats. Immunohistochemistry revealed that ghrelin cells were sparsely distributed in the proper gastric glands in all species. The number of ghrelin cells per unit area in hamsters was significantly lower than that in rats. Immunoelectron microscopy detected ghrelin immunolabelling in granules in the X-type endocrine cells. However, the diameter of granules in the hamsters was significantly smaller than that in the mice and rats. Gastric ghrelin contents were determined by radioimmunoassay, and levels in the hamsters were significantly lower than those in mice and rats. The results from mice were identical to those from rats. In conclusion, gastric ghrelin cells in mice and hamsters are characterized by X-type endocrine cells, as has been observed in rats. However, the data indicated that gastric ghrelin production was lower in hamster than in mouse or rat.
authors.affiliation: Department of Veterinary Anatomy, Faculty of Agriculture, Research Center for Life Science Resources, Kagoshima University, Korimoto, Japan. yabu@vet.agri.kagoshima-u.ac.jp
authors.forename: Akira
authors.initials: A
authors.lastname: Yabuki
authors.forename: Toshimichi
authors.initials: T
authors.lastname: Ojima
authors.forename: Masayasu
authors.initials: M
authors.lastname: Kojima
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Nishi
authors.forename: Hiroharu
authors.initials: H
authors.lastname: Mifune
authors.forename: Mitsuharu
authors.initials: M
authors.lastname: Matsumoto
authors.forename: Ryozo
authors.initials: R
authors.lastname: Kamimura
authors.forename: Taku
authors.initials: T
authors.lastname: Masuyama
authors.forename: Syusaku
authors.initials: S
authors.lastname: Suzuki
mesh_terms: D000818:Animals; D006224:Cricetinae; D005748:Gastric Fundus / Q000737:chemistry* / Q000166:cytology*; D054439:Ghrelin; D008297:Male; D008647:Mesocricetus; D051379:Mice; D008813:Mice, Inbred ICR; D016253:Microscopy, Immunoelectron; D036361:Peptide Hormones / Q000032:analysis*; D011863:Radioimmunoassay / Q000379:methods; D051381:Rats; D017208:Rats, Wistar; D013045:Species Specificity
chemical_list: D054439:Ghrelin; D036361:Peptide Hormones