The effects of endogenous hypergastrinemia and hypogastrinemia on the exocrine and endocrine rat pancreas.

The effects of endogenous hypergastrinemia and hypogastrinemia on the exocrine and endocrine pancreas were studied in the rat. Hypergastrinemia was induced by antral exclusion, and hypogastrinemia by antral resection. The studies were made 14 weeks after surgery. The total weight of the pancreas was increased both in hypergastrinemic and hypogastrinemic animals, due to hypertrophy of the exocrine cells. In contrast, the volume and total weight of the pancreatic islets were decreased. There was no numerical difference in the A-, D-, PP-cells between the hyper- and hypogastrinemic animals, respectively, and the controls. The number of insulin-producing (B-) cells was certainly reduced after the induction of hypogastrinemia. There was, however, signs of increased B-cell activity, which might contribute to an underestimation of the number of B-cells with the technique used. These findings do not support the hypothesis that antral gastrin has trophic influence on either exocrine or endocrine pancreas.