Effect of somatostatin on insulin-induced hypoglycemia in man

In order to study the interaction of insulin and somatostatin on glucose regulation in the posthypoglycemic phase of a somatostatin infusion we have applied a bolus of i.v. insulin to healthy subjects receiving a continuous infusion of somatostatin. Glucose, insulin and counterregulatory hormones were determined. Somatostatin suppressed the growth hormone and glucagon responses to hypoglycemia but did not augment the hypoglycemic action of insulin. In contrast, the K-value for the decrease in blood glucose was significantly lower in the presence of somatostatin. Thus, the interaction of insulin and somatostatin on glucose metabolism is complex and time-dependent. While the peptide potentiates the action of insulin during the first hour of somatostatin infusion, it counteracts if after two hours. As somatostatin has currently been introduced in the therapy of upper gastrointestinal bleedings, these effects of the peptide must be taken into consideration.