Endotoxin-induced disseminated intravascular coagulation in nonpregnant rats. A new experimental model.

Disseminated intravascular coagulation as indicated by glomerular capillary thrombosis was induced in unprepared virgin rats by the infusion of endotoxin. Dose-time curves revealed that the minimal amount necessary was 0.9 mg and the time required was 3 hours. A marked difference in susceptibility between the summer and winter seasons was observed, the animals being more sensitive in the former. The platelet count decreased in a dose-related manner; however, there was no difference between an infusion and injection regimen. There was no difference in platelet numbers between the animals who had fibrin deposits and those free of fibrin. Plasma hemoglobin increased by 500% in those animals who developed glomerular fibrin deposition and the hematocrit decreased less profoundly. The data demonstrate that unprepared virgin rats can be used as an experimental model for studying glomerular fibrin deposition, the hallmark of what is generally referred to as the generalized Shwartzman reaction, if endotoxin is continuously infused rather than injected.