Portal somatostatin reponds to intragastric glucose: Effects of streptozotocin diabetes.

Changes in somatostatin levels in portal plasma in response to intragastric glucose loading were examined in normal controls and streptozotocin diabetic rats of one week duration.The mean (±SEM) basal level of somatostatin was more significantly elevated in diabetic rats (401±62 pg/ml) than in controls (171±13 pg/ml). However, no significant difference in somatostatin concentrations 30 min after glucose loading was found between diabetic and control animals (587±113 vs. 443±47 pg/ml). Glucose loading caused a significant elevation of somatostatin in controls, but not in diabetic rats.These results suggest a physiologic role of somatostatin in nutrient homeostasis, and that abnormalities in D cell function are present in streptozotocin diabetes of short duration.