BIOCHEMICAL ASSAY OF SERUM BILE-ACIDS - METHODS AND APPLICATIONS

Immunoassays and bioluminescence assays of bile acids in serum have pr ovided relatively simple and sensitive methods for assessing the conce ntration of selected sub-groups of bile acids. However, these assays d o not provide full data for each of the individual bile acids. The rec ent development of sensitive techniques such as high-performance liqui d chromatography (HPLC) and gas-liquid chromatography-mass spectrometr y (GLC-MS) have made possible the separation and quantification of fre e and conjugated bile acids in biological samples. Several studies hav e demonstrated the value of individual serum bile acid levels and bile acid ratios when assessing the hepatic function of experimental anima ls treated with various hepatoxic agents, and in humans with various h epatic disorders. Current data show that individual serum bile acids a re more sensitive and specific as early predictors of hepatic injury, and are an accurate independent prognostic indicator. These studies ha ve provided further insight into the various determinants of serum bil e acid levels in physiological and pathological conditions affecting t he liver. Future studies using these techniques and perhaps monoclonal antibodies, fast atom bombardment-mass spectrometry (FAB-MS) and nucl ear magnetic resonance (NMR) for bile acid assays may provide both res earcher and clinician with a reliable, sensitive and specific indicato r of hepatic injury.