Acute peritonitis in a C57BL/6 mouse model of peritoneal dialysis

Studies using animal models of peritoneal dialysis (PD) have commonly induced acute peritonitis by intraperitoneal (IP) administration of lipopolysaccharide (LPS). We compared the effects of peritonitis induced by IP administration of either LPS or zymosan on inflammatory parameters [dialysate leukocyte counts and dialysate concentrations of prostaglandin E2 (PGE2) and vascular endothelial growth factor (VEGF)] and peritoneal transport of fluid, small solutes (glucose), and macromolecules (total protein) in a mouse model of PD. Eighteen hours after induction of peritonitis, mice were studied by injecting 2 mL of 4.25% dextrose-containing PD solution into the peritoneal cavity for a 2-hour dwell. Concentrations of glucose, total protein, PGE2, and VEGF were determined in the dialysate effluent. Acute peritonitis induced by IP administration of LPS induced changes in peritoneal transport similar to those observed during clinical PD, but without a significant increase in the dialysate leukocyte count. In contrast, acute peritonitis induced by IP administration of zymosan induced a large increase in dialysate leukocyte count, more substantial changes in peritoneal transport, and increases in dialysate PGE2 and VEGF concentrations. We conclude that acute peritonitis induced by IP administration of zymosan in the mouse may be a more relevant model for clinical PD, because it produces substantial changes in peritoneal transport and leukocyte migration into the peritoneal cavity.