Inhibition by somatostatin of glucose induced 3′: 5′‐monophosphate (Cyclic AMP) accumulation and insulin release in isolated pancreatic islets of the rat

Effect of GIP on the secretion of insulin and somatostatin and the accumulation of cyclic AMP in vitro in the rat

“…The secretory response of the B-cell thus reached a maximum at a lower concen¬ tration of GIP than that of the D-cell (Fig. Since we have previously shown that somatostatin depresses cAMP as well as insulin responses in isolated islets (Claro et al 1977;Efendic et al 1976), it seems possible that an augmented D-cell secretion induced by a high concentration of GIP may have inhibited insulin secretion in our islets, perhaps by an intra-islet i.e. These findings are reminiscent of those obtained with different concentrations of glucagon as a stimu¬ lator of insulin and somatostatin release (Kadowaki et al 1979).…”

On the Inhibitory Effects of Somatostatin on Arginine-Induced Insulin and Growth Hormone Secretion in Man: Influence of Aminophylline

“…Studies carried out with isolated rat pancreatic islets and perfused dog pancreas {Claro et al Efendic, Grill and Luft 1975;Osorio et al 1979) seem to indicate that the inhibitory action of SRIF on glucose-induced IRI release is dependent on the effect SRIF exerts on the adenylcyclase-cAMP system. However, this is not completely clear, since administration of dibutyryl cAMP to humans in addition to SRIF is not followed by the usual IRI secretion {Peracchi et al 1976).…”

Studies on the Mechanism of Somatostatin Action on Insulin Release in Man

“…We have recently demonstrated that somatostatin, in as large a dose as 500 ng/ml of incubation medium, induces a parallel suppression of the release from isolated rat islets of insulin and cyclic AMP (Efendic et al 1975). This might suggest that somatostatin inhibits insulin release by interfering with the accumulation of the nucleotide within the /i-cells.…”