title: Effect of different times of administration of a single ethanol dose on insulin action, insulin secretion and redox state.
abstract: OBJECTIVE
  Ethanol (EtOH) can affect glucose metabolism by altering the redox state, insulin-mediated glucose uptake and insulin secretion. We sought to determine the effects of an acute oral EtOH load on insulin secretion and glucose tolerance and the importance of a different timing of administration relative to a glucose load.
  
  
  METHODS
  Eleven subjects underwent a frequently sampled intravenous glucose tolerance test (FSIGT) on three occasions in random order. In one, EtOH was given 50 min 'before' the FSIGT; on the second, the same amount was administered 6 min after the glucose pulse ('during' study); on the third no EtOH was given.
  
  
  RESULTS
  Blood EtOH peaked at 4.43+/-0.24 mmol/l (mean +/- SD) in the 'during' and 4.16+/-0.31 mmol/l in the 'before' study. No differences were noticed in S(I), the index of insulin sensitivity, or in S(G), the glucose effectiveness, between the 'before', 'during' and control studies. There were no differences in the first-phase insulin secretion between the three studies but a significant increase in the sensitivity to glucose of second-phase dynamic insulin response, phi2, in the 'before' (0.062+/-0.036 pmol x min(-2) x (mg(-1) x dl(-1))(-1)) and 'during' (0.063+/-0.059) studies, compared to the control study (0.017+/-0.010, P<0.05) was observed. No differences were observed in the hepatic extraction of insulin. In the 'before' study, there was a significant decline in NEFA (non-esterified fatty acid) concentration from the baseline (mean 602+/-51 micromol/l) to the O min value (mean 353+/-37, P<0.01). During the FSIGT, the mean plasma NEFA concentration was significantly lower in the 'before' and in the 'during' than in the control study.
  
  
  CONCLUSIONS
  An acute oral EtOH load does not impair glucose metabolism, at least in part because of an increased second-phase insulin secretion. Since this effect is observed irrespective of whether EtOH is consumed either before or during the glucose load, the existence of a priming effect is questioned.
authors.affiliation: Ospedale Civile di San Vito al Tagliamento, Italy.
authors.forename: N
authors.initials: N
authors.lastname: Trojan
authors.forename: P
authors.initials: P
authors.lastname: Pavan
authors.forename: E
authors.initials: E
authors.lastname: Iori
authors.forename: M
authors.initials: M
authors.lastname: Vettore
authors.forename: M C
authors.initials: MC
authors.lastname: Marescotti
authors.forename: I A
authors.initials: IA
authors.lastname: Macdonald
authors.forename: A
authors.initials: A
authors.lastname: Tiengo
authors.forename: G
authors.initials: G
authors.lastname: Pacini
authors.forename: A
authors.initials: A
authors.lastname: Avogaro
mesh_terms: D000328:Adult; D000428:Alcohol Drinking / Q000097:blood / Q000503:physiopathology*; D001786:Blood Glucose / Q000378:metabolism*; D002096:C-Peptide / Q000097:blood; D000431:Ethanol / Q000097:blood / Q000494:pharmacology*; D005230:Fatty Acids, Nonesterified / Q000097:blood; D005260:Female; D005951:Glucose Tolerance Test; D006801:Humans; D007328:Insulin / Q000097:blood / Q000378:metabolism / Q000502:physiology*; D000078790:Insulin Secretion; D007700:Kinetics; D008297:Male; D010084:Oxidation-Reduction; D012016:Reference Values; D012984:Software; D013997:Time Factors
chemical_list: D001786:Blood Glucose; D002096:C-Peptide; D005230:Fatty Acids, Nonesterified; D007328:Insulin; D000431:Ethanol