title: Insulin secretion and action.
abstract: Recent advances in insulin secretion indicate that pertussis toxin abolishes the inhibition by alpha 2 adrenoceptor activation of insulin release by the pancreas. Pertussis toxin adenosine diphosphate (ADP) ribosylates an inhibitory guanine nucleotide-binding protein (Ni) involved in inhibition of adenylate cyclase. The decrease in cyclic adenosine monophosphate (AMP) by epinephrine may account for its inhibition of insulin release. Insulin interaction with its receptor results in an increase in the tyrosine protein kinase activity of the receptor. Second messengers for insulin are generated, hexose transport is accelerated, and a cyclic AMP-independent protein kinase is activated that phosphorylates at serinethreonine residues. The activity of membrane-bound enzymes such as adenylate cyclase and Ca2+-Mg2+-ATPase is affected. The relative importance of these effects of insulin in its regulation of cellular metabolism remains to be established.
mesh_terms: D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; D000273:Adipose Tissue / Q000378:metabolism; D000818:Animals; D001427:Bacterial Toxins / Q000494:pharmacology; D001692:Biological Transport; D002118:Calcium / Q000502:physiology; D002395:Catecholamines / Q000502:physiology; D002462:Cell Membrane / Q000378:metabolism; D000242:Cyclic AMP / Q000502:physiology; D004789:Enzyme Activation; D005947:Glucose / Q000502:physiology; D006601:Hexoses / Q000378:metabolism; D006801:Humans; D007328:Insulin / Q000378:metabolism* / Q000502:physiology; D000078790:Insulin Secretion; D007515:Islets of Langerhans / Q000187:drug effects / Q000378:metabolism; D010455:Peptides / Q000302:isolation & purification; D037342:Pertussis Toxin; D010743:Phospholipids / Q000378:metabolism; D010750:Phosphoproteins / Q000378:metabolism; D010766:Phosphorylation; D021382:Protein Sorting Signals; D011972:Receptor, Insulin / Q000378:metabolism; D013004:Somatostatin / Q000502:physiology; D010566:Virulence Factors, Bordetella
chemical_list: D037361:Adenylate Cyclase Toxin; D000067956:Adenylyl Cyclase Inhibitors; D001427:Bacterial Toxins; D002395:Catecholamines; D006601:Hexoses; D007328:Insulin; D010455:Peptides; D010743:Phospholipids; D010750:Phosphoproteins; D021382:Protein Sorting Signals; D010566:Virulence Factors, Bordetella; D013004:Somatostatin; D000242:Cyclic AMP; D037342:Pertussis Toxin; D011972:Receptor, Insulin; D005947:Glucose; D002118:Calcium