Mathematical modeling of stimulus-secretion coupling in the pancreatic beta-cell. III. Glucose-induced inhibition of calcium efflux.
The inhibitory effect of glucose upon 45Ca efflux from prelabeled pancreatic islets was simulated in a mathematical model for Ca2+-cyclic AMP interaction in the process of glucose-induced insulin release. At variance with a previous interpretation, it was postulated that glucose inhibits 45Ca efflux by facilitating the uptake of the cation by the vacuolar system. The latter facilitation did not hinder glucose from provoking a rapid accumulation of cytosolic Ca2+ and, hence, insulin release. The postulated facilitation was also suitable in simulating the effect of glucose upon 45Ca efflux, uptake, and intracellular distribution in the pancreatic islets.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D003600:Cytosol / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology*; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D008433:Mathematics; D008954:Models, Biological; D014617:Vacuoles / Q000378:metabolism
D005947:Glucose; D002118:Calcium