Liver microsomal bilirubin UDP-glucuronyltransferase disturbances in bile duct ligated rats.

The activity of bilirubin UDP-Glucuronyltransferase was determined in microsomes from normal and bile duct ligated rats. It was measured after 2 and 8 days following bile duct ligation and compared with normal rats. A decrease of 33% in the total enzyme activity was observed on day 2; a fall of 70% was founded on day 8. Bilirubin diglucuronide represented approximately 20% of total conjugates in both groups of cholestatic rats, as compared with 65% found in normals. It was concluded that bilirubin microsomal conjugating capacity is markedly altered during cholestasis. This can be attributed to microsomal membrane damage produced by stagnant bile.