Bilirubin conjugation and biliary bilirubin excretion after intravenous bilirubin injection in dogs.
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.
Usui
R
R
First Department of Surgery, Tohoku University School of Medicine, Sendai.
Ise
H
H
Kitayama
O
O
Moriyasu
A
A
Abe
Y
Y
Satoh
S
S
Inoue
H
H
Hayasaka
H
H
Hirama
Y
Y
Honda
H
H
D000818:Animals; D001646:Bile / Q000378:metabolism / Q000502:physiology; D001647:Bile Acids and Salts / Q000378:metabolism; D001663:Bilirubin / Q000008:administration & dosage / Q000378:metabolism* / Q000493:pharmacokinetics; D004285:Dogs; D007275:Injections, Intravenous
D001647:Bile Acids and Salts; D001663:Bilirubin