title: No effect of melatonin on oxidative stress after laparoscopic cholecystectomy: a randomized placebo-controlled trial.
abstract: BACKGROUND
  Melatonin, an endogenous circadian regulator, also has antioxidant and anti-inflammatory properties. The aim of this study was to evaluate the antioxidative effect of melatonin in patients undergoing laparoscopic cholecystectomy.
  
  
  METHODS
  Patients were randomized to receive 10 mg melatonin or placebo during surgery. Blood samples for analysis of malondialdehyde (MDA), ascorbic acid (AA), total ascorbic acid (TAA) dehydroascorbic acid (DHA) and C-reactive protein (CRP) were collected pre-operatively and at 5 min, 6 h and 24 h after operation.
  
  
  RESULTS
  Twenty patients received melatonin and 21 patients received placebo during surgery. No significant differences were observed between the groups in the oxidative stress variables MDA, TAA, AA and DHA or in the inflammatory variable CRP (repeated-measures ANOVA, P>0.05 for all variables).
  
  
  CONCLUSIONS
  Administration of 10 mg melatonin did not reduce variables of oxidative stress in patients undergoing elective laparoscopic cholecystectomy.
authors.affiliation: Department of Surgical Gastroenterology, University of Copenhagen, Herlev Hospital, Herlev, Denmark. bulentkucukakin@hotmail.com
authors.forename: B
authors.initials: B
authors.lastname: Kücükakin
authors.forename: M
authors.initials: M
authors.lastname: Klein
authors.forename: J
authors.initials: J
authors.lastname: Lykkesfeldt
authors.forename: R J
authors.initials: RJ
authors.lastname: Reiter
authors.forename: J
authors.initials: J
authors.lastname: Rosenberg
authors.forename: I
authors.initials: I
authors.lastname: Gögenur
mesh_terms: D000328:Adult; D000368:Aged; D017081:Cholecystectomy, Laparoscopic; D004311:Double-Blind Method; D006801:Humans; D008550:Melatonin / Q000494:pharmacology*; D008875:Middle Aged; D018384:Oxidative Stress / Q000187:drug effects*; D011446:Prospective Studies
chemical_list: D008550:Melatonin