Effects of somatostatin on the biosynthesis and release of insulin from isolated pancreatic islets.

The glucose-stimulated insulin release of pancreatic islets isolated either from normal mice or from mice with the obese-hyperglycemic syndrome (genotype ob/ob) was inhibited by somatostatin in the concentration range 10(-2) - 10(-4) mM. Islets prepared from the obese-hyperglycemic mice appeared most sensitive and there was a strong inhibitory action on the insulin release irrespective of whether the islets were exposed to somatostatin directly after isolation or after five days in tissue culture. There was, however, no effect of somatostatin on the glucose-stimulated insulin biosynthesis of the mouse islets. Neither was there an effect on the insulin biosynthesis of isolated islets from three days old rats, despite a previous report to the contrary. It is concluded that somatostatin does not affect the insulin biosynthesis of isolated islets at concentrations which inhibit insulin release.