[Experimental study on the changes of bile acids and their fractions after liver ischemia]

Serum bile acids and their fractions in the systemic and portal vein were measured after liver ischemia of 0, 30, 60, and 90 minutes with extracorporeal venous bypass in 20 dogs. The following results were obtained: 1) Total concentration of bile acids in the serum rapidly increased during the ischemic phase because of extinction of enterohepatic circulation due to flow of portal blood into the systemic circulation. 2) Portal blood flow decreased after recirculation of the liver, and this decrease was more severe in the 90-minute ischemic group than in the 30- and 60-minute groups. 3) After recirculation, increased bile acids were taken up by hepatocytes, and their concentrations in the systemic vein decreased markedly. The 90-minute ischemic group had a significantly slower rate of decrease compared to the 30- and 60-minute groups. This was due to its significantly lower portal blood flow rate. 4) Hepatocyte dysfunction was suggested in the 90-minute ischemic group, since the uptake of bile acids into the liver, especially dihydroxy- and deconjugated bile acids, significantly decreased. These results indicate that measurement of serum bile acids and their fractions is useful for estimating the liver function after liver ischemia.