The Mechanism of Trauma-Induced Inhibition of Insulin Release

Abstract

The insulin response to a glucose load (1 gm/kg body weight, I.V.) was studied in intact rats and 90 min after injury in a Noble-Collip drum. Control rats responded with a rise of immunoreactive insulin in plasma, while injured animals failed to increase plasma insulin in spite of increased plasma glucose concentration. Alpha adrenergic blockade with phentolamine 2 mg/kg, or phenoxybenzamine, 5 mg/kg, one hour before injury did not improve the insulin secretory response to glucose in injured rats: Only in rats adrenomedullectomized 6 weeks before the experiment was the insulin response to glucose administration the same in the injured and the control groups. These results indicate that adrenomedullary catecholamines play a role in the trauma induced inhibition of insulin release.

Key words

Insulin Response to Glucose - Alpha Adrenergic Blockade - Phentolamine - Phenoxybenzamine - Reserpine - Catecholamines - Corticosterone - Stress - Noble-Collip Drum Trauma - Rat