title: Prolactin modulates survival and cellular immune functions in septic mice.
abstract: BACKGROUND
  The immunomodulatory properties of the pituitary hormone prolactin have been demonstrated. It was proposed that prolactin is important in maintaining normal immune response in several pathological states. We investigated the effect of prolactin administration on the survival and cellular immune functions during systemic inflammation.
  
  
  METHODS
  Male NMRI mice were subjected to laparotomy (LAP) or sepsis induced by cecal ligation and puncture (CLP). Mice were treated with either saline (LAP/saline; CLP/saline) or prolactin (LAP/PRL, CLP/RPL; 4 mg/kg s.c.). Survival of septic mice was determined 24 and 48 h after CLP. Forty-eight hours after the septic challenge, the proliferative capacity, cytokine release (IL-2, IL-6, IFN-gamma) and apoptosis of splenocytes were determined. Additionally, monitoring of circulating leukocyte distribution was performed (WBC; CD3+, CD4+, CD8+, B220+, NK1.1+, F4/80+ cells by FASCan).
  
  
  RESULTS
  CLP was accompanied by a mortality of 47% and induced a decrease in splenocyte proliferation and apoptosis rate. Administration of prolactin significantly increased the mortality of septic mice (81%). This was paralleled by a further decrease of splenocyte proliferation and an increased splenocyte apoptosis. In addition, administration of prolactin augmented the sepsis-induced inhibition of IL-2 release, attenuated the sepsis-induced inhibition of IFN-gamma release, and did not affect the release of IL-6. However, prolactin did not affect the sepsis-induced changes of circulating leukocyte subpopulations.
  
  
  CONCLUSIONS
  We conclude that prolactin has profound immunomodulatory properties and that administration of prolactin in pharmacological doses is associated with a decreased survival and an inhibition of cellular immune functions in septic mice.
authors.affiliation: Department of Trauma Surgery, University Hospital of Essen, Essen, Germany. reineroberbeck@hotmail.com
authors.forename: Reiner
authors.initials: R
authors.lastname: Oberbeck
authors.forename: Daniel
authors.initials: D
authors.lastname: Schmitz
authors.forename: Klaus
authors.initials: K
authors.lastname: Wilsenack
authors.forename: Mark
authors.initials: M
authors.lastname: Schüler
authors.forename: Claudia
authors.initials: C
authors.lastname: Biskup
authors.forename: Manfred
authors.initials: M
authors.lastname: Schedlowski
authors.forename: Dieter
authors.initials: D
authors.lastname: Nast-Kolb
authors.forename: Michael S
authors.initials: MS
authors.lastname: Exton
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects / Q000502:physiology; D002432:Cecum / Q000601:surgery; D016207:Cytokines / Q000032:analysis; D007111:Immunity, Cellular / Q000187:drug effects*; D007415:Intestinal Obstruction; D007416:Intestinal Perforation; D008026:Ligation; D008297:Male; D051379:Mice; D023421:Models, Animal; D010907:Pituitary Hormones / Q000276:immunology / Q000494:pharmacology*; D011388:Prolactin / Q000276:immunology / Q000494:pharmacology*; D018805:Sepsis / Q000276:immunology*; D016019:Survival Analysis
chemical_list: D016207:Cytokines; D010907:Pituitary Hormones; D011388:Prolactin