Effect of Insulin on Glucose- and Arginine-Stimulated Somatostatin Secretion from the Isolated Perfused Rat Pancreas*

The effects of exogenous insulin on somatostatin secretion from the isolated perfused rat pancreas have been investigated in the presence of 5.6 mM glucose and when somatostatin secretion was stimulated by either glucose (16.7 mM) or arginine (20 mM). Insulin (15 mU/ml) significantly and rapidly suppressed glucose- and arginine-stimulated somatostatin release. However, at 5.6 mM glucose and, in the absence of other stimulators of somatostatin release, insulin had no effect on the somatostatin secretion rate.