Glucose inhibits insulin release induced by Na+ mobilization of intracellular calcium.
45Ca2+ incorporated in response to glucose was selectively mobilized from the beta-cell-rich pancreatic islets of ob/ob-mice after raising the intracellular Na+ by removal of K+ or addition of ouabain or veratridine. Also studies of insulin release indicated opposite effects of glucose and Na+ on the intracellular sequestration of calcium. The fact that glucose inhibits insulin release induced by raised intracellular Na+ indicates that this sugar can lower the cytoplasmic [Ca2+]. The concept of a dual action of glucose on the cytoplasmic [Ca2+]. The concept of a dual action of glucose on the cytoplasmic [Ca2+] might well explain previous observations of an inhibitory component in the glucose action on the 45Ca2+ efflux.
D000818:Animals; D002118:Calcium / Q000378:metabolism*; D005947:Glucose / Q000494:pharmacology*; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism*; D007700:Kinetics; D051379:Mice; D008820:Mice, Obese; D010042:Ouabain / Q000494:pharmacology; D012964:Sodium / Q000494:pharmacology*; D014701:Veratridine / Q000494:pharmacology
D007328:Insulin; D010042:Ouabain; D014701:Veratridine; D012964:Sodium; D005947:Glucose; D002118:Calcium