Low-grade intravascular coagulation and reticuloendothelial function.

The present study evaluated the influence of experimentally produced intravascular coagulation on reticuloendothelial (RE) stability. Intravascular coagulation was initiated by the intraperitoneal injection of bovine thrombin (500 U/100 g body wt) into male rats. RE function was evaluated by the vascular clearance of an 131I-labeled RE test colloid. Thrombin injection resulted in a transient (0.5-2 h) (P less than .05) depression of the phagocytic index (K) with maximal depression at 1 h postthrombin challenge. The phagocytic index was unaltered after injection of saline or heat-inactivated thrombin. Vascular clearance depression was primarily due to a 37% decrease (P less than .001) in hepatic Kupffer cell colloid clearance and was associated with increments in lung (82%) and marrow (100%) colloid localization with no splenic alterations. While intravascular coagulation was associated with decreased hepatic blood flow at 30 min and 120 min, sinusoidal flow was normal during maximum RE impairment at 60 min. The in vivo clearance depression was not reflected as an intrinsic Kupffer cellular deficit when evaluated in an in vitro system. The results indicate a transient RE dysfunction during intravascular coagulation, the mechanism of which remains to be elucidated.