The role of the peptide hormone gastrin in stimulating gastric acid secretion is well established.Mature amidated gastrin is processed from larger peptide precursor forms.Increasingly these processing intermediates, such as glycine-extended gastrin (G-Gly) and progastrin, have been shown to have biological activities of their own, often separate and complementary to gastrin.
Although G-Gly is synthesized and secreted by gastric antral G-cells, the physiological functions of this putative mediator are unclear.Gastrin and cholecystokinin (CCK) stimulate the secretion of somatostatin from gastric D-cells as part of the Course a pied - Femme - Vetements - Chandail - Zip brosse feedback control of gastric acid.In this study the effect of G-Gly and gastrin on the release of somatostatin from rabbit fundic D-cells was examined.
D-cells were obtained by collagenase-EDTA digestion and elutriation and cultured for 48 Nutritionals Accessories hours.With a 2 hour exposure to the peptides, gastrin but not G-Gly stimulated somatostatin release.Treatment of D-cells for 24 hours with gastrin or G-Gly individually, significantly enhanced subsequent basal as well as CCK- and GLP-1-stimulated somatostatin release.
Twenty four hours exposure to gastrin combined with G-Gly synergistically enhanced basal and agonist-stimulated somatostatin release and cellular somatostatin content.Gastrin and G-Gly may be important in the longer term regulation of D-cell function.