title: Pancreatic islet cells: a model for calcium-dependent peptide release.
abstract: In mammals the concentration of blood glucose is kept close to 5 mmol∕l. Different cell types in the islet of Langerhans participate in the control of glucose homeostasis. β-cells, the most frequent type in pancreatic islets, are responsible for the synthesis, storage, and release of insulin. Insulin, released with increases in blood glucose promotes glucose uptake into the cells. In response to glucose changes, pancreatic α-, β-, and δ-cells regulate their electrical activity and Ca(2+) signals to release glucagon, insulin, and somatostatin, respectively. While all these signaling steps are stimulated in hypoglycemic conditions in α-cells, the activation of these events require higher glucose concentrations in β and also in δ-cells. The stimulus-secretion coupling process and intracellular Ca(2+) ([Ca(2+)](i)) dynamics that allow β-cells to secrete is well-accepted. Conversely, the mechanisms that regulate α- and δ-cell secretion are still under study. Here, we will consider the glucose-induced signaling mechanisms in each cell type and the mathematical models that explain Ca(2+) dynamics.
authors.forename: Bernat
authors.initials: B
authors.lastname: Soria
authors.forename: Eva
authors.initials: E
authors.lastname: Tudurí
authors.forename: Alejandro
authors.initials: A
authors.lastname: González
authors.forename: Abdelkrim
authors.initials: A
authors.lastname: Hmadcha
authors.forename: Franz
authors.initials: F
authors.lastname: Martin
authors.forename: Angel
authors.initials: A
authors.lastname: Nadal
authors.forename: Ivan
authors.initials: I
authors.lastname: Quesada