Secretion of somatostatin from the normal and diabetic pancreas - Studies in vitro

Abstract

The role of cyclic AMP in the control of somatostatin release may be primarily that of a modulator without being an essential factor for initiation of somatostatin release. Much work is, however, still required to elucidate the exact nature of the role of cyclic AMP in the secretory mechanism of the D cell. All of the present evidence, however, points to a key regulatory role for calcium in the cascade of events that proceeds to the somatostatin secretion [24, 26, 30-33]. The data indicate that the changes in somatostatin secretion provoked by alterations in the extra-and intracellular levels of Na+ and K+ are secondary to changes in the intracellular level of calcium in the D cell. Caution should, however, be exercised in deducing from the results from cation fluxes in whole islets because of the mixed cell population studied. They cannot be assumed to represent the responses of the D cell alone because these cells make up only 5-15% of the total cell mass in the islet. © 1980 Springer-Verlag.