Plasma disappearance of sulfobromophthalein or indocyanine green in unconjugated hyperbilirubinemia.

Unconjugated hyperbilirubinemia as occurs in Gunn rats did not affect the plasma disappearance of sulfobromophthalein (BSP) or indocyanine green (ICG). The simultaneous injection of bilirubin and ICG decreased the plasma disappearance of ICG apparently by decreasing hepatic uptake. The data suggest that although bilirubin, ICG and BSP bind to the intracellular hepatic transport protein ligandin one cannot achieve conditions in intact rats to demonstrate effects of competitive interaction with ligandin that affect plasma kinetics of these substances.