Baumgartner U, Miyai K, Hardison W G
Am J Physiol. 1986 Oct;251(4 Pt 1):G431-5. doi: 10.1152/ajpgi.1986.251.4.G431.
Differing patterns of taurodeoxycholate (TDC) metabolism and biliary excretion were studied with a forward-and-backward perfusion model of the isolated rat liver. Livers were perfused with 8 microM TDC via either the portal vein (forward) or the hepatic vein (backward). Bile was collected, total bile acids measured enzymatically, and bile composition determined by high-pressure liquid chromatography and thin-layer chromatography. During backward perfusion 48% of infused TDC was metabolized to taurocholate (TC) and 22.0% to other minor TDC metabolites. During forward perfusion, however, only 16% of administered TDC was metabolized to TC and 6.5% to minor metabolites. Total bile acid output was similar for both forward and backward perfusions. The kinetics of biliary bile acid excretion also differed between forward and backward perfusion. The time necessary for 50% excretion of labeled TDC and its metabolites was 3.5 +/- 0.45 min during forward and 18 +/- 3.50 min during backward perfusion, a time difference of 14.5 min. The greater biotransformation of TDC during backward perfusion could be explained by its longer intracellular residence. The reason for the delayed excretion of TDC during backward perfusion is unknown.
采用离体大鼠肝脏前后向灌注模型，研究了牛磺脱氧胆酸盐（TDC）代谢和胆汁排泄的不同模式。通过门静脉（正向）或肝静脉（反向）用8 microM TDC灌注肝脏。收集胆汁，酶法测定总胆汁酸，并通过高压液相色谱和薄层色谱法测定胆汁成分。在反向灌注期间，48%注入的TDC代谢为牛磺胆酸盐（TC），22.0%代谢为其他次要TDC代谢物。然而，在正向灌注期间，仅16%给予的TDC代谢为TC，6.5%代谢为次要代谢物。正向和反向灌注的总胆汁酸输出相似。正向和反向灌注之间胆汁酸排泄的动力学也不同。标记的TDC及其代谢物50%排泄所需的时间在正向灌注期间为3.5±0.45分钟，在反向灌注期间为18±3.50分钟，时间差为14.5分钟。反向灌注期间TDC更大的生物转化可以用其更长的细胞内停留时间来解释。反向灌注期间TDC排泄延迟的原因尚不清楚。
