A) Primary hepatocytes were isolated from hUGT1*1 mice and treated with either estrogen (20 μg/ml), progesterone (50 μg/ml), or dexamethasone (DEX-1 μM). After 24 hours RNA was isolated and UGT1A1 gene expression was determined by RT and Q-PCR. Ct values from RT and Q-PCR were normalized to the housekeeping gene CPH, and calculated as fold induction over the expression levels of cells treated with vehicle control. B) Primary hepatocytes were exposed to different concentrations of dexamethasone. After 24 hours, RNA was isolated and UGT1A1 gene expression monitored by RT and Q-PCR. A sample of total cell extract was also prepared and used for immunodetection of UGT1A1 and GAPDH by Western blot analysis. C) Isolated hepatocytes were exposed to dexamethasone (1 μM) or corticosterone (20 μM) for 24 h, followed by RT and Q-PCR analysis and Western blot analysis to detect human UGT1A1expression, and GAPDH blotting was used as loading control.