Abstract
It has recently been demonstrated that bile acids are actually present in normal blood of humans and some experimental animals. In order for investigate the origin of those bile acids, 14C-dehydrocholic and 3H-7α, 12α-dihydroxy-3-oxocholanoic acids were injected into the portal vein of a rat provided with a bile fistula, through which different hydrostatic pressures were applied. The following data were obtained: 1. When 14C-dehydrocholic acid was injected into the rat under the maximum pressure corresponding to that of bile excretion (ca. 20cm H2O), radioactivity in blood was found for the most part in conjugated bile acid (s). 2. When 3H-7α, 12α-dihydroxy-3-oxocholanoic acid was injected into the rat under the maximum pressure mentioned above, radioactivity in blood was found to be the highest and, for the most part, was in conjugated bile acid; under a lower pressure (0-9cm H2O) applied to the choledocus, radioactivity in blood was found for the most part (60-70%) in free bile acids and the remainder in conjugated bile acids; the conjugated acid was identified as taurocholic acid, while the free acids were proved to be cholic acid and the injected material which remained unchanged.
Based on these data, it was concluded that some or most part of bile acid (s) in normal blood come directly from the liver cells through Disse's space (parapedesis).
