title: The concept of the immune-pineal axis tested in patients undergoing an abdominal hysterectomy.
abstract: OBJECTIVE
  Activation of the immune-pineal axis induces a transient reduction in nocturnal melatonin in the plasma during the proinflammatory phase of an innate immune response to allow the proper migration of leukocytes to the lesion site. This transient reduction should be regulated by inflammatory mediators, which are responsible for the fine-tuning of the process. In the present study, we measured the pre- and postoperative serum concentrations of melatonin, tumor necrosis factor (TNF) and cortisol in women who underwent an elective hysterectomy and correlated the variation in melatonin with postoperative pain.
  
  
  METHODS
  We evaluated 12 women who had an abdominal hysterectomy. Blood was collected at 10.00 and 22.00 h 1 week and 1 day before the surgery, on the 1st and 2nd days after the surgery and at 22.00 h on the day of the surgery.
  
  
  RESULTS
  On the night after the surgery, there was no melatonin detected at 22.00 h. High TNF levels were accompanied by a lower nocturnal melatonin output, higher postoperative pain according to a visual analog scale and the request of higher doses of analgesics. In addition, low cortisol levels were accompanied by a lower nocturnal melatonin output.
  
  
  CONCLUSIONS
  Our results confirm that the same antagonistic pattern between TNF and glucocorticoids observed in cultured pineal glands also occurs in humans. This integrative pattern suggests that the cross talk between the immune and endocrine system orchestrates longitudinal changes in pineal activity, reinforcing the hypothesis of an immune-pineal axis.
authors.affiliation: Post-Graduate Program in Medical Sciences, School of Medicine, Clinical Hospital of Porto Alegre, Brazil.
authors.forename: Mirella
authors.initials: M
authors.lastname: de Oliveira Tatsch-Dias
authors.forename: Rosa Maria
authors.initials: RM
authors.lastname: Levandovski
authors.forename: Izabel Cristina
authors.initials: IC
authors.lastname: Custódio de Souza
authors.forename: Marcelo
authors.initials: M
authors.lastname: Gregianin Rocha
authors.forename: Pedro Augusto Carlos
authors.initials: PA
authors.lastname: Magno Fernandes
authors.forename: Iraci L S
authors.initials: IL
authors.lastname: Torres
authors.forename: Maria Paz L
authors.initials: MP
authors.lastname: Hidalgo
authors.forename: Regina P
authors.initials: RP
authors.lastname: Markus
authors.forename: Wolnei
authors.initials: W
authors.lastname: Caumo
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D006854:Hydrocortisone / Q000097:blood / Q000276:immunology*; D007044:Hysterectomy / Q000379:methods; D007113:Immunity, Innate / Q000276:immunology*; D008550:Melatonin / Q000097:blood / Q000276:immunology*; D008875:Middle Aged; D010870:Pineal Gland / Q000276:immunology* / Q000378:metabolism; D014409:Tumor Necrosis Factor-alpha / Q000097:blood / Q000276:immunology*; D055815:Young Adult
chemical_list: D014409:Tumor Necrosis Factor-alpha; D008550:Melatonin; D006854:Hydrocortisone