Fig. 2.

Determination of UGT activity. A, RNA from TgUGT2B7 mouse liver was isolated, reverse-transcribed to cDNA, subcloned into a pcDNA3 expression vector, and heterologously expressed in COS-1 cells by transient transfections. After preparation of cell lysates, UGT activity was determined using HDCA as a substrate. UGT1A4-specific substrate amitriptyline was used as a negative control substrate. B, UGT activity was determined in liver microsomes prepared from TgUGT2B7 and wild-type mice (n = 4) using HDCA as substrate.