Comparison of the effect of somatostatin and an analogue, SMS 201-995, on gastrin and insulin secretion from isolated perfused rat stomach and pancreas.
The effects of a somatostatin analogue, SMS 201-995, and somatostatin-14 on gastrin and insulin release from the isolated perfused rat stomach and pancreas were studied. Equipotent effects were observed on the inhibition of basal gastrin release from the stomach. SMS 201-995 was approximately 14 times less effective than somatostatin-14 (molar basis) in the pancreas. At a high glucose concentration (17.6 mM), neither the analogue nor the peptide inhibited insulin release, but at a glucose concentration of 8.8 mM, there was significant inhibition. In the presence of 10 mM arginine plus glucose at a concentration of either 8.8 or 17.6 mM, insulin secretion was reduced by both SMS 201-995 and somatostatin-14 to levels obtained with glucose alone. However, when gastric inhibitory polypeptide (10 ng/ml) in the presence of 8.8 mM glucose was used to stimulate insulin release, somatostatin-14 completely inhibited the insulinotropic action of gastric inhibitory polypeptide while SMS 201-995 was without effect. Studies with this analogue suggest that arginine and gastric inhibitory polypeptide stimulate insulin release via different mechanisms.
D000818:Animals; D001120:Arginine / Q000494:pharmacology; D005749:Gastric Inhibitory Polypeptide / Q000494:pharmacology; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism; D005755:Gastrins / Q000378:metabolism*; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D008297:Male; D015282:Octreotide; D010179:Pancreas / Q000187:drug effects / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D011919:Rats, Inbred Strains; D013004:Somatostatin / Q000031:analogs & derivatives* / Q000494:pharmacology*
D005755:Gastrins; D007328:Insulin; D013004:Somatostatin; D005749:Gastric Inhibitory Polypeptide; D001120:Arginine; D015282:Octreotide