Tolbutamide stimulates gastric somatostatin release from isolated perfused rat stomach

The effect of tolbutamide on somatostatin release from the isolated perfused stomach was investigated in both normal and streptozotocin-diabetic rats. Tolbutamide (10, 100, and 1000 microgram/ml) evoked a significant and dose-dependent increase in gastric somatostatin release. The tolbutamide (100 microgram/ml)-induced gastric somatostatin secretion was not influenced by differences in glucose concentration (1.5, 5.5, and 16.5 mM) throughout the perfusion period. Tolbutamide (100 microgram/ml)-induced gastric somatostatin release in streptozotocin-diabetic rats was significantly higher than in normal rats. Thus, tolbutamide is a potent secretagogue for gastric somatostatin secretion, and this effect is more prominent in diabetic animals.