November 1, 2017 (Vol. 37, No. 19)
Non-transplant quality human livers donated for research are a common source of both cellular and subcellular material utilized in in vitro drug-metabolism studies. Researchers had previously shown that 1 mM allopurinol (a common ingredient in ice-cold perfusion and storage solutions) inhibits XO activity in human liver cytosol. Concerned that the exposure of human livers to allopurinol could lead to an underestimation of the contribution of XO in the metabolism of new chemical entities, pooled human liver S9 and cytosol subcellular fractions that have been prepared from tissue treated to preserve high AO (aldehyde oxidase) and XO (xanthine oxidase) activity are now available.