Characterization and species differences in gastric ghrelin cells from mice, rats and hamsters.
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.
Yabuki
Akira
A
Department of Veterinary Anatomy, Faculty of Agriculture, Research Center for Life Science Resources, Kagoshima University, Korimoto, Japan. yabu@vet.agri.kagoshima-u.ac.jp
Ojima
Toshimichi
T
Kojima
Masayasu
M
Nishi
Yoshihiro
Y
Mifune
Hiroharu
H
Matsumoto
Mitsuharu
M
Kamimura
Ryozo
R
Masuyama
Taku
T
Suzuki
Syusaku
S
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
D054439:Ghrelin; D036361:Peptide Hormones