Figure 2.

The antagonist effects of RAL and its analogues on ERα- and ERβ-mediated transcriptional activities. (a) CV-1 cells co-transfected with ERα (pcDNA3.1-hERα) and a luciferase reporter gene plasmid (ERE-MMTV-Luc) was treated with various concentrations of the compounds as listed. 17β-Oestradiol (E₂) was added 30 min later to give a final concentration of 10 nM (EC₈₀). The data presented are the percentage of the activity of each compound relative to that induced by E₂ at EC₈₀. Values in parentheses indicate respective IC₅₀ (nM) for each compound. Results represent an average of three independent measurements. (b) Experiments were performed as above, except that the cells were transfected with pSG5-hERβ. RAL, raloxifene. ^*P<0.05, ^**P<0.01 compared to RAL treatment.