title: Use of dynamic weight bearing as a novel end-point for the assessment of abdominal pain in the LPS-induced peritonitis model in the rat.
abstract: BACKGROUND
  Chronic pelvic pain (CPP) is defined as long-lasting and severe pelvic pain persisting over six months in cyclic or non-cyclic chronic manner. Various pathologic conditions like endometriosis, abdominal infections, intra-peritoneal adhesions or infection, underlie CPP which is often the leading symptom of the associated diseases. Pharmacological approaches addressing CPP are hampered by the absence of a straight-forward, objective, and reliable method for the assessment of CPP in rodents.
  
  
  METHODS
  In the presented study, the dynamic weight bearing system (DWB) was employed for the first time for the evaluation of pelvic pain in a rat model of LPS-induced peritonitis. Rats were pretreated with the COX-2 inhibitor rofecoxib and PGE2 levels were evaluated in peritoneal lavage.
  
  
  RESULTS
  DWB analysis revealed that rats treated with LPS showed a relief posture by a significantly increased weight distribution to the front when compared to vehicle-treated animals. This effect was prevented by rofecoxib treatment indicating the sensitivity of the model for pelvic pain related to peritonitis. Analysis of the PGE2 levels in the peritoneal fluid indicated a correlation with the relief posture intensity.
  
  
  CONCLUSIONS
  In contrast to others weight bearing approaches, the use of DWB allows evaluation of spontaneous posture changes as a consequence of pelvic pain.
  
  
  CONCLUSIONS
  Taken together, we were able to show, that DWB combined with LPS-induced peritonitis may deliver a new reliable animal model addressing pelvic pain with high construct validity (peritoneal inflammation), and face validity (pain related relief posture).
authors.affiliation: Global Drug Discovery - TRG Oncology/Gynecological Therapies, Bayer Healthcare Pharmaceuticals, Berlin, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Gruen
authors.affiliation: Global Drug Discovery - TRG Oncology/Gynecological Therapies, Bayer Healthcare Pharmaceuticals, Berlin, Germany.
authors.forename: Alexis
authors.initials: A
authors.lastname: Laux-Biehlmann
authors.affiliation: Global Drug Discovery - TRG Oncology/Gynecological Therapies, Bayer Healthcare Pharmaceuticals, Berlin, Germany.
authors.forename: Thomas M
authors.initials: TM
authors.lastname: Zollner
authors.affiliation: Global Drug Discovery - TRG Oncology/Gynecological Therapies, Bayer Healthcare Pharmaceuticals, Berlin, Germany. Electronic address: jens.nagel@bayer.com.
authors.forename: Jens
authors.initials: J
authors.lastname: Nagel
mesh_terms: D015746:Abdominal Pain / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology*; D000704:Analysis of Variance; D000818:Animals; D052246:Cyclooxygenase 2 Inhibitors / Q000627:therapeutic use; D015232:Dinoprostone / Q000378:metabolism; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D005260:Female; D007783:Lactones / Q000627:therapeutic use; D008070:Lipopolysaccharides / Q000633:toxicity; D010147:Pain Measurement; D010538:Peritonitis / Q000139:chemically induced / Q000150:complications* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D013450:Sulfones / Q000627:therapeutic use; D013997:Time Factors; D016474:Weight-Bearing
chemical_list: D052246:Cyclooxygenase 2 Inhibitors; D007783:Lactones; D008070:Lipopolysaccharides; D013450:Sulfones; C116926:rofecoxib; D015232:Dinoprostone
keywords: COX-2; Inflammation; PGE2; Pain; Pelvic; Weight bearing