| 内容提要: |
In this study, we chose UGT1A9 enzyme bags and mefenamic acid (which is reported to be a selective inhibitor for UGT1A9) to do an inhibitor assay. In order to illustrate the usefulness of the UGT enzyme bag activity assays we monitored the inhibitory potency of the known UGT inhibitor mefenamic acid and determined its IC50for UGT1A9 inhibition at 4.1 μM. While this value is somewhat lower than that (11.2 μM) reported for the inhibition of UGT1A9-dependent mycophenolic acid glucuronidation in HLMs, it must be taken into consideration that mycophenolic acid is not a specific substrate for UGT1A9. Therefore, contributions by other UGTs such as UGT2B7 are likely to play a role in HLMs and therefore account for the difference in IC50values. It is expected that the enzyme bag inhibitor assay should facilitate a screen for new UGT inhibitors |