Plasma Glucose and Insulin Responses to Glucagon and Arginine in Aston ob/ob Mice: Evidence for a Selective Defect in Glucose-Mediated Insulin Release

Summary

Fed adult obese hyperglycaemic (ob/ob) mice fail to produce a positive plasma insulin response to an intraperitoneal (ip) glucose challenge. The present study demonstrates that both fed and fasted ob/ob mice produce a marked positive plasma insulin response to an ip challenge by glucagon or arginine throughout the phases of development and regression of the ob/ob syndrome. These observations provide evidence that failure of the B-cells to respond to glucose in fed adult ob/ob mice cannot be attributed to inadequate amounts of releasable insulin. In addition, the results show that the B-cells of fed adult ob/ob mice do not incur a generalized defect of stimulus-recognition-secretion-coupling.

Key-Words:

Arginine - Glucagon - Obese Hyperglycaemic (ob/ob) Mice