Ultrastructural studies of experimental endotoxin shock in the liver and spleen: therapeutic effects of low-dose heparin on reticuloendothelial disturbances.

To determine the effects of low-dose heparin on the reticuloendothelial system in shock, rats were subjected to intraperitoneal administration of E coli endotoxin. Alterations such as degeneration and necrosis of the Kupffer cells and sinusoidal endothelial cells were observed in the livers of the non-heparin-treated animals 4 hours after the administration of the endotoxin. These changes progressed with time. Kupffer cells in the heparin-treated rats appeared undisturbed up to 8-12 hours post endotoxin challenge. Phagocytosis of cell remained slight in the heparin-treated rats. The mortality rate of the heparin-treated group was 10% with LD50 endotoxin (7.6 mg/kg). The mortality rate of the untreated control group 24 hours after administration was 50%. However, when endotoxin was administered in a dosage of 30 mg/kg (MLD), the mortality rate of the heparin-treated rats was 60%--10% greater than that of controls (P less than 0.05).