In vitro paracrine regulation of islet B-cell function by A and D cells.

In monolayer cultures of islet cells from neonatal rats, incubation of cells for 1 hour with either anti-somatostatin serum or anti-glucagon serum enhanced insulin release. The former appears to be due to neutralization of endogenously secreted somatostatin. The latter may be due to removal of a stimulatory effect of endogenously released glucagon upon somatostatin secretion. Thus, although exogenously added glucagon stimulates insulin secretion, the effect of endogenously released glucagon upon islet B cells is a restraining one which may be mediated through an effect upon D cells and their release of endogenous somatostatin.