The effects of ulinastatin on the reticuloendothelial system (RES) of rabbits in endotoxin shock.

Carbon clearance, concentration of fibronectin (Fn) in the blood and arterial ketone body ratio (AKBR) have been measured in the rabbit in order to evaluate the RES phagocytic activity and the effect of ulinastatin on it in endotoxin (ET) shock. The following results were obtained: 1) carbon deposition by ET injection was found in organs (lung and kidney) which did not show it in the control group. The reasons for this might be considered that the RES was blocked because of phagocytizing ET and tissue debris, so that the carbon which could not be processed by the RES spilled over and became clogged; 2) the RES phagocytic activity were found to decline from an early stage after injection of a lethal dose of ET due to a decline in Fn productivity and an increase in Fn consumption; and, 3) ulinastatin suppressed the decrease of Fn and the carbon deposition in the kidney in ET shock. These results are suggestive of the usefulness of ulinastatin as an anti-shock agent, preserving the RES phagocytic activity through the inhibition of Fn consumption.