Fig. 4.

Sex-dependent hormonal regulation of HNF-4α binding to the CYP3A4 promoter (ChIP assay) (A) and confirmation of the occupied HNF-4α-binding motif in the CYP3A4 promoter (Southern blotting) (B) in hepatocytes derived from adult men and women. The cells were exposed to either continuous dexamethasone alone (DEX), continuous GH alone, or both hormones (DEX+GH) for 5 d in culture, after which the hepatocytes were harvested and analyzed. Each data point is a mean ± sd for cells from six men, all treatments except DEX+GH, in which n = 5; six women, all treatments. *, P < 0.01 compares with the GH alone treatment of the same sex; †, P < 0.01 compares women with men exposed to the same hormone treatment. A representative ChIP blot (A) with its input control (albumin) and a Southern blotting (B) are presented in the figure.