A new animal model for human preeclampsia: ultra-low-dose endotoxin infusion in pregnant rats.

OBJECTIVE An animal model for preeclampsia was developed by means of an ultra-low-dose endotoxin infusion protocol in conscious pregnant rats. STUDY DESIGN Rats received a permanent jugular vein cannula on day 0 of pregnancy, through which endotoxin (1.0 micrograms/kg body weight) (n = 10) or saline solution (n = 6) was infused during 1 hour on day 14 of pregnancy. Blood pressure, albuminuria, and platelet counts were measured, and histopathologic studies was performed in these rats. RESULTS A significant increase of blood pressure (p < 0.05) and of urinary albumin excretion (p < 0.05) was observed in endotoxin-treated pregnant animals, in contrast to control pregnant rats receiving saline solution. Platelet coagulopathy was found and glomerular fibrinogen deposits could be detected only in the endotoxin-treated pregnant rats. In addition, the activity of the glomerular antithrombotic enzyme adenosine diphosphatase was decreased in endotoxin-treated pregnant rats compared with saline solution-treated pregnant rats. CONCLUSION Because histopathologic and clinical events in this model mimic predominant features of human preeclampsia, this model may enable further study into the pathophysiologic mechanisms of this complication of pregnancy.