The effect of bucolome on the biliary excretion of colchicine in the rat.

The biliary excretion of intravenously administered [14C]-colchicine was compared for 2 hr between control rats and rats treated with bucolome (5-n-butyl-1-cyclohexyl-2,4,6-trioxoperhydropyrimidine, 200 mg/kg, i.p.). In the first 10-min period after colchicine injection, the bile flow rate was 70 percent higher (p less than 0.01) in bucolome treated rats than in control rats. The bile flow rate in bucolome treated rats gradually decreased and 1 hr later, the difference between control and bucolome treated rats was no longer significant (p greater than 0.05). The percent of the administered colchicine dose recovered in the first 2 hr in bucolome treated rats given an i.v. injection of 70 or 700 micrograms/kg colchicine was significantly higher than in control rats. The difference was primarily due to the higher excretion rate in the former group in the first 10-min period. When the biliary radioactivity was examined by thin layer chromatography, it was found that the excretion of free colchicine was significantly increased in bucolome treated rats which accounted for the observed increase in the biliary excretion of radioactivity in bucolome treated rats. It was concluded that bucolome is effective in increasing the biliary excretion of free colchicine.