Hepatic transport and biliary excretion of sulfobromophthalein in aflatoxin B1-treated rats.

The effects of a single dose of aflatoxin B1 (AFB1) on sulfobromophthalein (BSP) plasma disappearance, hepatic transport maximum (Tm), and relative storage capacity (S), were examined in rats 48 hr after AFB1 injection. BSP plasma concentration decay was delayed, and the BSP biliary excretion was diminished in treated animals. S and Tm values were unaltered. However, the Tm was reached in treated rats at a higher infusion rate. A Lineweaver-Burk plot of BSP biliary excretion rate vs BSP serum concentration curve showed a higher apparent Km in the AFB1-treated rats.