胆汁色素に関する研究 第2編 硫酸抱合型bilirubinの腸管吸収に関する研究

Intestinal absorption of direct bilirubin was studied with chemically synthetic (3)H-bilirubin sulfate which was alkali-stable, and compared to that of commercial (3)H-bilirubin. (3)H-bilirubin sulfate and (3)H-bilirubin was loaded into three isolated intestinal segments, that is, the (isolated) duodenal segment, the (isolated) small intestinal segment and the (isolated) large intestinal segment of heterozygous Gunn rats and Wistar strain rats. After loading of bilirubins, biles and urines were collected at intervals of 2 hours up to 8 and from 8 to 24 hours. Radioactivity of the excreted biles and urines was studied and resulted as follows: 1) After loading of (3)H-bilirubin sulfate dissolved in physiological saline into the three each segment of Gunn rats or Wistar strain rats, ratios of the excreted radioactivity into bile were not significantly different between them. 2) After (3)H-bilirubin sulfate was dissolved in pool rat bile or physiological saline, the two each sample was loaded into the three each segment of Gunn rats. The difference of the excreted ratio was not significant between them. 3) In case of loading of (3)H-bilirubin sulfate into the small intestinal segment and the large intestinal segment in comparison of the duodenal segment, the ratio of excreted radioactivity into the bile was higher. 4) After (3)H-bilirubin sulfate or (3)H-bilirubin was dissolved in pool rat bile, the sample was loaded into the three each segment of Wistar strain rats. The biliary excretion within 24 hours following the loading of (3)H-bilirubin sulfate into the duodenal, small intestinal and large intestinal segment were 2.58, 4.41 and 4.33%, and loading (3)H-bilirubin, were 8.55, 7.35 and 3.70%, respectively. Difference between the excretion ratio of (3)H-bilirubin sulfate loading group and (3)H-bilirubin loading group was significant when loaded into the duodenal and small intestinal segment. But there was no difference between the excretion ratio of (3)H-bilirubin sulfate loading and (3)H-bilirubin loading into the large intestinal segment. 5) It was suggested that (3)H-bilirubin sulfate was absorbed from intestinal mucosa and excreted into biliary tract without any change of its nature.