title: Loss of inverse relationship between pulsatile insulin and glucagon secretion in patients with type 2 diabetes.
abstract: OBJECTIVE
  In patients with type 2 diabetes, glucagon levels are often increased. Furthermore, pulsatile secretion of insulin is disturbed in such patients. Whether pulsatile glucagon secretion is altered in type 2 diabetes is not known.
  
  
  METHODS
  Twelve patients with type 2 diabetes and 13 nondiabetic individuals were examined in the fasting state and after mixed meal ingestion. Deconvolution analyses were performed on insulin and glucagon concentration time series sampled at 1-min intervals.
  
  
  RESULTS
  Both insulin and glucagon were secreted in distinct pulses, occurring at ∼5-min intervals. In patients with diabetes, postprandial insulin pulse mass was reduced by 74% (P < 0.001). Glucagon concentrations were increased in the patients during fasting and after meal ingestion (P < 0.05), specifically through an increased glucagon pulse mass (P < 0.01). In healthy subjects, the increase in postprandial insulin levels was inversely related to respective glucagon levels (P < 0.05). This relationship was absent in the fasting state and in patients with diabetes.
  
  
  CONCLUSIONS
  Glucagon and insulin are secreted in a coordinated, pulsatile manner. A plausible model is that the postprandial increase in insulin burst mass represses the corresponding glucagon pulses. Disruption of the insulin-glucagon interaction in patients with type 2 diabetes could potentially contribute to hyperglucagonemia.
authors.affiliation: Department of Medicine I, St. Josef-Hospital, Ruhr-University Bochum, Bochum, Germany.
authors.forename: Björn A
authors.initials: BA
authors.lastname: Menge
authors.forename: Lena
authors.initials: L
authors.lastname: Grüber
authors.forename: Signe M
authors.initials: SM
authors.lastname: Jørgensen
authors.forename: Carolyn F
authors.initials: CF
authors.lastname: Deacon
authors.forename: Wolfgang E
authors.initials: WE
authors.lastname: Schmidt
authors.forename: Johannes D
authors.initials: JD
authors.lastname: Veldhuis
authors.forename: Jens J
authors.initials: JJ
authors.lastname: Holst
authors.forename: Juris J
authors.initials: JJ
authors.lastname: Meier
mesh_terms: D000368:Aged; D001786:Blood Glucose / Q000032:analysis; D003924:Diabetes Mellitus, Type 2 / Q000503:physiopathology*; D005215:Fasting; D005260:Female; D005934:Glucagon / Q000378:metabolism*; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D008297:Male; D008875:Middle Aged; D019518:Postprandial Period
chemical_list: D001786:Blood Glucose; D007328:Insulin; D005934:Glucagon