title: Spatial distribution of osteoblast activating peptide in the rat stomach.
abstract: Osteoblast activating peptide (OBAP) was previously reported to be expressed in the rat stomach and to have a vital role in osteogenesis, but its distribution in rat stomach has not been determined. Thus, the aim of the present study was to identify the cell types expressing OBAP in the rat stomach. The stomachs of twelve 10-to-11-week-old male Jc1:SD rats were used. Samples were collected for immunohistochemistry, immunoelectron microscopy and dot blot assay. Immunohistochemical investigation revealed that OBAP was distributed mainly in parietal cells without any expression in chief cells, X/A-like cells or enterochromaffin-like cells. Moreover, OBAP-immunopositive cells were observed mainly in the upper and lower parts of the gastric gland. Significantly high optical density of immunopositive cells was observed in the upper and lower gastric gland regions. The dot blot assay confirmed that OBAP is secreted by parietal cells and that it is present in the gastric gland lumen. Immunoelectron microscopy demonstrated that OBAP was confined to the mitochondrial inner membrane within parietal cells and that the number of mitochondria in the upper and lower parts of the gastric epithelium was significantly larger than the number in the middle part of the gastric epithelium. Based on the results, it was concluded that OBAP is mainly produced by mitochondria of parietal cells in the upper and lower parts of the gastric epithelium. Moreover, the presence of OBAP in the gastric gland lumen suggests an exocrine mechanism of release.
authors.affiliation: Department of Veterinary Anatomy, Faculty of Agriculture, Tottori University, Tottori, Japan; Department of Histology and Cytology, Faculty of Veterinary Medicine, Damanhour University, Damanhour, Egypt.
authors.forename: Ahmed E
authors.initials: AE
authors.lastname: Noreldin
authors.affiliation: Department of Veterinary Anatomy, Faculty of Agriculture, Tottori University, Tottori, Japan.
authors.forename: Maina
authors.initials: M
authors.lastname: Sogabe
authors.affiliation: Department of Veterinary Biochemistry, Faculty of Agriculture, Tottori University, Tottori, Japan; Department of Basic Veterinary Science, United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan.
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Yamano
authors.affiliation: Department of Veterinary Anatomy, Faculty of Agriculture, Tottori University, Tottori, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Uehara
authors.affiliation: Department of Basic Veterinary Science, United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan; Department of Anatomy and Embryology, Faculty of Veterinary Medicine, South Valley University, Qena, Egypt.
authors.forename: Mohamed A A
authors.initials: MA
authors.lastname: Mahdy
authors.affiliation: Department of Histology and Cytology, Faculty of Veterinary Medicine, Damanhour University, Damanhour, Egypt.
authors.forename: Mohamed A
authors.initials: MA
authors.lastname: Elnasharty
authors.affiliation: Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Damanhour University, Damanhour, Egypt.
authors.forename: Ahmed
authors.initials: A
authors.lastname: Sayed-Ahmed
authors.affiliation: Department of Veterinary Anatomy, Faculty of Agriculture, Tottori University, Tottori, Japan.
authors.forename: Katsuhiko
authors.initials: K
authors.lastname: Warita
authors.affiliation: Department of Veterinary Anatomy, Faculty of Agriculture, Tottori University, Tottori, Japan; Department of Basic Veterinary Science, United Graduate School of Veterinary Science, Yamaguchi University, Yamaguchi, Japan. Electronic address: y-hosa@muses.tottori-u.ac.jp.
authors.forename: Yoshinao Z
authors.initials: YZ
authors.lastname: Hosaka
mesh_terms: D000818:Animals; D005753:Gastric Mucosa / Q000378:metabolism*; D008297:Male; D008928:Mitochondria / Q000502:physiology; D009928:Organ Specificity; D010455:Peptides / Q000378:metabolism*; D051381:Rats; D013270:Stomach / Q000166:cytology
chemical_list: D010455:Peptides; C552696:osteoblast activating peptide, rat
keywords: OBAP; Parietal cell; Rat; Stomach