No effect of melatonin on oxidative stress after laparoscopic cholecystectomy: a randomized placebo-controlled trial.
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.
Kücükakin
B
B
Department of Surgical Gastroenterology, University of Copenhagen, Herlev Hospital, Herlev, Denmark. bulentkucukakin@hotmail.com
Klein
M
M
Lykkesfeldt
J
J
Reiter
R J
RJ
Rosenberg
J
J
Gögenur
I
I
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
D008550:Melatonin