The role of the liver lymphatics in the transport of non-erythroid bilirubin during different stages of experimental cholestasis.
The role of the liver lymphatics in the regurgitation of bilirubin during the different stages of cholestasis has been a matter of debate. Earlier studies have shown that 14C-bilirubin injected intravenously one hour after induction of cholestasis was rapidly and completely cleared from the blood and appeared in the thoracic duct lymph in high concentration. During chronic cholestasis the injected 14C-bilirubin was delivered directly back to the blood after conjugation in the liver. The aim of the present study was to investigate the role of the lymphatics in the transport of non-erythroid bilirubin (NEB), a metabolic product of certain tissue haemes, produced mainly in the liver. The study was carried out in dogs. Five dogs were studied in the first hours following bile duct obstruction, and five others after at least one week of cholestasis. 14C-delta-aminolevulinic acid was given as a NEB precursor. In contrast to the results obtained with 14C-bilirubin injection, evidence for a delivery of conjugated labelled NEB directly to the blood during acute cholestasis was found. The concentration curves for NEB and non-NEB radioactivity in the thoracic duct lymph indicated the presence of a secondary biliolymphatic regurgitation. In chronic cholestasis no evidence for such a biliolymphatic regurgitation of NEB was found.
D000208:Acute Disease; D000818:Animals; D001663:Bilirubin / Q000097:blood / Q000378:metabolism*; D002779:Cholestasis / Q000378:metabolism*; D002908:Chronic Disease; D004285:Dogs; D008099:Liver / Q000378:metabolism; D008196:Lymph / Q000032:analysis; D008208:Lymphatic System / Q000502:physiology*
D001663:Bilirubin