Release of somatostatin from rodent antral mucosae maintained in organ culture.
Somatostatin secretion was investigated from rodent antral mucosal biopsies maintained in organ culture. Under control conditions, the somatostatin secretory output was fairly constant, with each biopsy releasing a mean value of 29.1 +/- 7.5 pg of hormone over a 15-min period. Incubation of the mucosa in medium containing 5% peptone directly induced a 20-fold increase in medium somatostatin levels to 622.5 +/- 15.5 pg/ml. In contrast, a peptone dialysate was a weaker stimulant of hormone release, inducing a three- to fourfold increase in medium somatostatin concentration. Additionally, it was determined that a peptic hydrolysate of bovine serum albumin was a significantly more potent in vitro stimulant of somatostatin secretion than the intact undigested molecule. These results suggest that the amino acid and peptide constituents of these proteinaceous substances are the major stimulants of somatostatin release in vitro. It is presently uncertain whether this direct peptone-induced release of somatostatin from antral mucosal explants can account for the previously reported [Am. J. Physiol. 235 (Endocrinol. Metab. Gastrointest. Physiol. 4): E410-E415, 1978] gastrin secretory "off response" to the same agent, because addition of exogenous somatostatin to the medium failed to block this peptone-induced gastrin secretory response.
D000818:Animals; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism*; D005755:Gastrins / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008297:Male; D009924:Organ Culture Techniques; D010461:Peptones / Q000494:pharmacology; D011863:Radioimmunoassay; D051381:Rats; D012710:Serum Albumin, Bovine / Q000494:pharmacology; D013004:Somatostatin / Q000378:metabolism*
D005755:Gastrins; D010461:Peptones; D012710:Serum Albumin, Bovine; D013004:Somatostatin