Difference in the effect of bucolome on the hepatic transport maximum of sulfobromophthalein and indocyanine green.

The effects of bucolome (BC, 1-cyclohexyl-5-n-butyl-2,4,6-trioxoperhydropyrimidine, a non-steroid antiinflammatory agent), a potent choleretic, on the maximal biliary excretion rates (Tm) of sulfobromophthalein (BSP) and indocyanine green (ICG) were investigated in rats. With continuous infusion of BSP or ICG, Tm and bile flow rate in control rats and rats given BC (40--100 min after 20 mg/100 g body weight i.p. injection) were compared. The BSP Tm was not significantly different in control and BC administered rats (BC rats), while the bile flow rate and endogenous bile salts excretion rate were significantly higher in BC rats. On the other hand, ICG Tm was significantly higher in BC rats, although ICG concentration in bile was significantly lower in BC rats. The rates of the rise in plasma concentration of the dyes were significantly lower in BC rats. However, the plasma concentration of ICG was significantly higher in BC rats at corresponding time intervals than in control rats throughout the experimental period. The difference in the effect of BC on the transport of these two dyes indicates variability in the regulatory mechanisms for hepatic anion transport.