Effect of food ingestion on intestinal glucagon-like immunoreactivity (GLI) secretion in normal and gastrectomized subjects.

This work was undertaken to compare the intestinal GLI responses to oral glucose (1.75 g/kg, 25% sol.), to a carbohydrate-rich meal (carbohydrate content about 1.75 g/kg) and to a protein meal (250-400 g grilled lean beef) in normal (n = 6) and gastrectomized (n = 6) subjects. As expected, after glucose administration the elevation of plasma GLI was more pronounced in the gastrectomy group (approximately 500% above baseline) than in the controls (approximately 75% above baseline). However, the gastrectomized patients responded to the carbohydrate meal with a very slight elevation of circulating GLI (approximately 45% above baseline), similar to that found in the controls (approximately 70% above baseline). After the protein meal, a small increase of GLI was also observed in both groups. In conclusion, in gastrectomized subjects the ingestion of natural foodstuffs is followed by a normal elevation of plasma GLI, thereby suggesting the exclusion of this factor from involvement in the constellation of postgastrectomy syndrome. In these patients, the exaggerated rise in GLI after oral glucose is not representative of increments after physiological stimuli.