Glucagon secretion in subjects with prediabetes, diabetes mellitus and obesity.

The blood glucagon concentration (fasting and in insulin hypoglycemia) was determined by radioimmunoassay in diabetic patients, relatives of diabetic patients with a normal glucose tolerance test, patients with obesity and a group of normal weight subjects. The index of glucagon rise above the fasting level and glucagon release rate were estimated. In relatives of diabetic and obese patients the initial blood glucagon concentration did not differ from that of healthy subjects. However, during insulin hypoglycemia, glucagon secretion was significantly reduced, and in relatives of diabetic patients it also proved to be delayed. A comparison of glucagon and somatostatin changes in the above mentioned patients allows to suggest participation of the somatostatin mechanism in disorders of glucagon secretion.