title: Demonstration of [D-Ala2]deltorphin I-like immunoreactivity in mucosal epithelial cells of the rat gastrointestinal tract.
abstract: Using a specific antiserum to [D-Ala2]deltorphin I (DADTI), a delta-opioid receptor ligand, the localization of positive structures was studied in rat gastrointestinal tract by immunocytochemistry. Immunoreactive staining was not detected in the stomach, colon, or neuronal elements of any gastrointestinal tissue. However, positive cells were distributed in the mucosal epithelium of the small intestine, including the duodenum, jejunum, and ileum. The density of positive cells was highest at a proximal part of the jejunum and was gradually decreased toward the duodenum or the distal end of the intestine. These positive cells had spindle-like somata that tended to locate more closely to the lumen compared with nonimmunoreactive cells. Some of the positive cells extended cytoplasmic basal processes toward the lamina propria. Immunoelectron microscopy revealed that positive reaction products occurred within the secretory granules as well as in the cytoplasm. Because these positive granules were frequently observed in the apical cytoplasm beneath the microvilli, it is suggested that the DADTI-like molecule(s) may be secreted to the lumen.
authors.affiliation: Department of Anatomy, Shiga University of Medical Science, Japan.
authors.forename: M
authors.initials: M
authors.lastname: Fujimiya
authors.forename: K
authors.initials: K
authors.lastname: Okumiya
authors.forename: T
authors.initials: T
authors.lastname: Renda
authors.forename: H
authors.initials: H
authors.lastname: Kimura
authors.forename: T
authors.initials: T
authors.lastname: Maeda
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000918:Antibody Specificity; D003594:Cytoplasmic Granules / Q000737:chemistry; D005753:Gastric Mucosa / Q000737:chemistry* / Q000166:cytology; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000737:chemistry* / Q000166:cytology; D008297:Male; D016253:Microscopy, Immunoelectron; D008969:Molecular Sequence Data; D009842:Oligopeptides / Q000276:immunology / Q000302:isolation & purification*; D018847:Opioid Peptides / Q000276:immunology / Q000302:isolation & purification*; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution
chemical_list: D009842:Oligopeptides; D018847:Opioid Peptides; C060208:deltorphin I, Ala(2)-