title: Evidence that muscarinic potentiation of insulin release is initiated by an early transient calcium entry.
abstract: The increased insulin release induced by carbamoylcholine (CbCh) in pancreatic islets requires the presence of extracellular Ca2+. Intracellular recordings demonstrate that CbCh produces a transient increase in Ca2+ channel activity lasting from 30 to 60 s. Thereafter activity decreased to levels lower than in controls. When extracellular Ca2+ was present during this initial period, the stimulatory effects of CbCh were not different from those in which Ca2+ was present throughout. These experiments suggest that during muscarinic potentiation of insulin release extracellular calcium is only needed in the first minute.
mesh_terms: D000818:Animals; D002118:Calcium / Q000378:metabolism*; D002217:Carbachol / Q000494:pharmacology*; D004553:Electric Conductivity; D005947:Glucose / Q000494:pharmacology; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007473:Ion Channels / Q000187:drug effects / Q000502:physiology*; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism / Q000502:physiology*; D007700:Kinetics; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice
chemical_list: D007328:Insulin; D007473:Ion Channels; D002217:Carbachol; D005947:Glucose; D002118:Calcium