title: Myeloperoxidase response to peritonitis in an experimental model.
abstract: BACKGROUND
  Patients with peritonitis often exhibit systemic manifestations of sepsis, especially in the lungs. The aim of the present study was to evaluate the local and systemic effects of the neutrophil response to peritonitis in a rat model.
  
  
  METHODS
  Fifty Wistar rats were randomized to either a control group or a peritonitis group (5 mg zymosan intraperitoneal). Groups of five animals were killed at 4, 18, 24, 48 and 96 h for evaluation of the morphology of the peritoneum (mesothelial imprint), the number and phenotype of cells within peritoneal fluid (flow cytometry), and myeloperoxidase activity within the peritoneal fluid and distant organs (enzyme assay).
  
  
  RESULTS
  Zymosan produced macroscopic evidence of peritonitis and on microscopy there was disruption of peritoneal mesothelial cells. This was accompanied by an influx of neutrophils between 4 and 48 h (P < 0.001) and macrophages between 48 and 96 h (P < 0.001). There was also an increase in myeloperoxidase activity within peritoneal fluid between 4 and 48 h (P < 0.05), the lung at 4 h (P < 0.01) and the liver at 48 h (P < 0.001).
  
  
  CONCLUSIONS
  The present study has confirmed the validity of using zymosan to create a low-morbidity model of peritonitis. Besides the anticipated peritoneal response, there were distant effects of neutrophil activation within the lungs and liver. In the future, strategies that modulate neutrophil activation within these organs might play a useful adjunctive role in the management of patients with peritonitis.
authors: Department of Surgery, The University of Western Australia, Perth, Western Australia, Australia.
authors: Veronica
authors: V
authors: Yao
authors: Rosalie
authors: R
authors: McCauley
authors: Deborah
authors: D
authors: Cooper
authors: Cameron
authors: C
authors: Platell
authors: John C
authors: JC
authors: Hall
mesh_terms: D000818:Animals; D008297:Male; D009504:Neutrophils / Q000502:physiology*; D010538:Peritonitis / Q000139:chemically induced / Q000201:enzymology* / Q000276:immunology*; D009195:Peroxidase / Q000378:metabolism*; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D015054:Zymosan
chemical_list: D015054:Zymosan; D009195:Peroxidase