[Studies on the relation between late dumping syndrome and glucagon responses to glucose]

Abstract

This study was planned in pursuit of the relation between glucagon responses to glucose and the late dumping syndrome. Clinically, 75 g oral glucose tolerance test to seven late dumpers, ten gastrectomized patients and ten normal subjects were performed. And experimentary, 20 ml 25% glucose was put into small intestinal blind loops prepared in dogs, which were made the jejunum region and then the ileum region. 1. The mean oral glucose tolerance curve in gastrectomized patients was oxyhyperglycemic, and this tendency was seen in late dumpers. But, for only late dumpers, the low blood glucose concentration which was under 50 mg/dl appeared within one and half to three hours after oral glucose load. 2. The change of serum IRI in gastrectomized patients displayed the initial hyperinsulinemia, that was similar in late dumpers. 3. Pancreatic glucagon (GI) levels were within normal limits in normal subjects and late dumpers, but were significantly increased in gastrectomized patients. 4. Enteroglucagon (gutGLI) levels were not so increased in normal subjects, but were significantly increased in gastrectomized patients and late dumpers as well. 5. GutGLI levels were increased only by putting into the ileum loop. But hypersecretion of gutGLI did not affect the blood glucose curve and the change of serum IRI significantly. These results described above suggest that the pathogenesis of the hypoglycemia in the late dumping syndrome may be responsible for no hypersecretion of GI, for some reason, to prevent hypoglycemia against hyperinsulinemia with oxyhyperglycemia, and that gutGLI may not play so important part in the regulation of the blood glucose level.