ABSTRACT: This study was undertaken to investigate the bilirubin clearance, bilirubin conjugation and biliary bilirubin excretion after an intravenous single bilirubin injection (5 mg/kg or 10 mg/kg) in 10 mongrel dogs. Serum total bilirubin concentration increased after the bilirubin injection, and then it immediately decreased. Biliary excretion of loaded bilirubin induced a rapid increase of the bile total bilirubin concentration and bilirubin-monoconjugate. In the 10 mg/kg group, the increase was larger than in the 5 mg/kg group and remained high up to 4 hr after injection, whereas in the 5 mg/kg group these bile components tended to decrease and returned to the preinjection levels within 4 hr. The total bile acid concentration in the bile remained unchanged in both groups. The bile flow did not change in the 5 mg/kg group, but in the 10 mg/kg group it decreased after bilirubin loading. Significantly positive correlations were observed between total bilirubin and bilirubin monoconjugate concentrations in bile both before and 1 hr after injection, but the slopes of regression lines were markedly different from each other. These results suggest that a bilirubin load surpassing the conjugating capacity of the hepatocytes increases bile bilirubin monoconjugate and also enhances the conjugating activity in the liver.
The Tohoku Journal of Experimental Medicine 11/1991; 165(2):67-77. · 1.24 Impact Factor