Mathematical modelling of cyclic AMP-Ca2+ interactions in pancreatic islets.
A mathematical model is proposed to account for the interactions between Ca2+ and cyclic AMP in the process of glucose-induced insulin release. This model allows simulation of experimental findings such as the glucose-induced accumulation of cyclic AMP in islet cells, the calcium dependency of the latter accumulation, the time course of 45Ca net uptake by the islets exposed to glucose and/or a phosphodiesterase inhibitor, the stimulation of insulin release by glucose, the suppression of such a release at low extracellular Ca2+ concentration and its amplification by phosphodiesterase inhibitors, the restoration of a significant secretory response to glucose in islets deprived of Ca2+ but exposed to a phosphodiesterase inhibitor, and the usual relationship between 45Ca net uptake and insulin release. All these data refer to studies performed over a 90-min incubation. The model is not suitable, however, to simulate the rapid response of the islet cells during the first few minutes that follow a change in the environment of the islets.
D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D000242:Cyclic AMP / Q000378:metabolism / Q000502:physiology*; D003600:Cytosol / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000378:metabolism*; D008433:Mathematics; D008954:Models, Biological
D007328:Insulin; D000242:Cyclic AMP; D005947:Glucose; D002118:Calcium; D015056:1-Methyl-3-isobutylxanthine