title: The Effect of Circadian Melatonin Levels on Inflammation and Neurocognitive Functions Following Coronary Bypass Surgery.
abstract: OBJECTIVE
  In this study, the relationship between the plasma levels of melatonin and intercellular adhesion molecule-1 (ICAM-1), which plays role in several intercellular interactions including inflammatory and immune responses, and early neurocognitive functions associated with ischaemia-reperfusion injury during open heart surgery is examined.
  
  
  METHODS
  Forty patients who were to undergo elective coronary artery bypass grafting (CABG) were divided into two groups, those who underwent their operations at 8 AM (group I; n = 20) and those who underwent their operations at 1 PM (group II; n = 20). Blood samples were collected prior to surgery (S1), when the aortic cross clamp was removed (S2) and 4 (S3) and 24 h after the surgery (S4). Neuropsychiatric assessment was conducted one day before and seven days after surgery.
  
  
  RESULTS
  Melatonin levels measured during and after surgery were also significantly higher in Group 1. ICAM-1 levels were significantly lower in Group 1 at S2 and S3. Significant deterioration was observed in postoperative neurocognitive function compared with preoperative functions in Group 2 more than Group 1.
  
  
  CONCLUSIONS
  We hypothesise that the greater preservation of neurocognitive functions in the morning patients is associated with elevated melatonin levels, which reduce the damage from ischaemia-reperfusion injury.
authors.affiliation: Department of Neurology, Faculty of Medicine, University of Gaziantep, Turkey.
authors.forename: Sırma
authors.initials: S
authors.lastname: Geyik
authors.forename: Remzi
authors.initials: R
authors.lastname: Yiğiter
authors.forename: Aylin
authors.initials: A
authors.lastname: Akçalı
authors.forename: Hayati
authors.initials: H
authors.lastname: Deniz
authors.forename: Abidin
authors.initials: A
authors.lastname: Murat Geyik
authors.forename: Mehmet
authors.initials: M
authors.lastname: Ali Elçi
authors.forename: Erhan
authors.initials: E
authors.lastname: Hafız
mesh_terms: D002940:Circadian Rhythm; D003072:Cognition Disorders / Q000097:blood*; D001026:Coronary Artery Bypass; D005260:Female; D006801:Humans; D007249:Inflammation / Q000097:blood; D018799:Intercellular Adhesion Molecule-1 / Q000097:blood*; D008297:Male; D008550:Melatonin / Q000097:blood*; D008875:Middle Aged; D009483:Neuropsychological Tests; D011446:Prospective Studies; D015427:Reperfusion Injury / Q000097:blood; D012307:Risk Factors
chemical_list: D018799:Intercellular Adhesion Molecule-1; D008550:Melatonin