title: Transmembrane ion distribution and insulin secretion.
abstract: The sodium dependence of insulin release was studied with the in vitro perfused principal islet of channel catfish. When extracellular sodium was replaced with choline, glucose-induced insulin release and glucose enhancement of arginine-induced insulin release were selectively abolished. Lowering the extracellular pH from 7.6 to 7.1 had a similar selective effect on glucose-induced insulin release. It is suggested that the Na:H antiport is responsible for the sodium dependence of insulin release and that a lowered cytosolic pH preferentially inhibits the glucose sensing mechanism.
mesh_terms: D000818:Animals; D002352:Carrier Proteins / Q000378:metabolism; D002397:Catfishes; D002462:Cell Membrane / Q000378:metabolism; D005947:Glucose / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism*; D007515:Islets of Langerhans / Q000187:drug effects / Q000502:physiology*; D012964:Sodium / Q000378:metabolism / Q000494:pharmacology; D017923:Sodium-Hydrogen Exchangers
chemical_list: D002352:Carrier Proteins; D007328:Insulin; D007473:Ion Channels; D017923:Sodium-Hydrogen Exchangers; D012964:Sodium; D005947:Glucose