Aspects of Oscillatory Insulin Secretion
Slow oscillations of human insulin secretion have been observed during the last couple of decades. They may be explained either by an unstable insulin/glucose feedback mechanism or in terms of an intrapancreatic pacemaker. In the present paper, a simulation model of the insulin/glucose feedback system is presented which exhibits self-sustained oscillations for realistic parameter combinations when a constant glucose infusion is simulated. Entrainment of the oscillations occurs when an oscillatory rather than a constant glucose infusion is simulated, which suggests that the presence of the oscillations can be explained by the insulin/glucose feedback mechanism. The design and results of clinical experiments performed in non-diabetic humans are described which verity the simulation results, in that entrainment is also experimentally achieved. Finally, additional simulation results are presented which show that the system can have coexisting solutions, and potential clinical implications hereof are discussed.
KeywordsInsulin Secretion Plasma Insulin Glucose Infusion Slow Oscillation Insulin Secretion Rate
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