title: Release of gastric inhibitory polypeptide from cultured canine endocrine cells.
abstract: Canine intestinal duodenal and jejunal epithelial cell preparations enriched for endocrine cells were obtained by sequential collagenase digestion and centrifugal elutriation and maintained in culture for a 40-h period. Adherent cells contained a total cell content (TCC) of 11.5 +/- 2.5 ng (mean +/- SE) immunoreactive gastric inhibitory peptide (IRGIP)/well and 1.4 +/- 0.2 ng immunoreactive somatostatin (IRS)/well. Release experiments were performed by incubation of the cells with various stimuli over a 2-h period. Basal release of IRGIP in 5 mM glucose-5 mM K+ was 2.7 +/- 0.4% TCC. Incubation with concentrations of K+ > 20 mM or glucose > 15 mM significantly increased IRGIP release, as did the addition of a somatostatin immunoneutralizing antibody to the basal media. The addition of the Ca2+ ionophore, A-23187 (10 microM), or the adenylate cyclase activator, forskolin (100 microM), resulted in an IRGIP output greater than four times basal. Porcine gastrin-releasing peptide (GRP), at 1-100 nM, significantly stimulated IRGIP release in a concentration-dependent fashion. IRS release was increased significantly by 55 mM K+, 20 mM glucose, 10 microM A-23187, 100 nM GRP, or 100 microM forskolin.
authors.affiliation: Department of Physiology, University of British Columbia, Vancouver, Canada.
authors.forename: T J
authors.initials: TJ
authors.lastname: Kieffer
authors.forename: A M
authors.initials: AM
authors.lastname: Buchan
authors.forename: H
authors.initials: H
authors.lastname: Barker
authors.forename: J C
authors.initials: JC
authors.lastname: Brown
authors.forename: R A
authors.initials: RA
authors.lastname: Pederson
mesh_terms: D000818:Animals; D000001:Calcimycin / Q000494:pharmacology; D002469:Cell Separation; D002478:Cells, Cultured; D005576:Colforsin / Q000494:pharmacology; D004285:Dogs; D004702:Endocrine Glands / Q000166:cytology / Q000378:metabolism*; D005260:Female; D005749:Gastric Inhibitory Polypeptide / Q000378:metabolism*; D019886:Gastrin-Releasing Peptide; D005947:Glucose / Q000494:pharmacology; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000166:cytology / Q000378:metabolism; D007421:Intestine, Small / Q000166:cytology / Q000378:metabolism; D008297:Male; D010455:Peptides / Q000494:pharmacology; D011188:Potassium / Q000494:pharmacology; D013004:Somatostatin / Q000378:metabolism; D013552:Swine
chemical_list: D010455:Peptides; D005576:Colforsin; D000001:Calcimycin; D013004:Somatostatin; D005749:Gastric Inhibitory Polypeptide; D019886:Gastrin-Releasing Peptide; D005947:Glucose; D011188:Potassium