Beginning 1 wk after ovariectomy, animals were given a single daily sc injection of R-DPN (2.0 mg/kg) in a total volume of 0.2 ml.

Human endometrial cancer-1 (HEC-1) cells, or U2OS, a human osteosarcoma derived cell line were grown in MEM containing phenol red, 5% calf serum and 100 μg/ml penicillin/streptomycin. Cells were then cultured at least six days in phenol red-free MEM supplemented with 5% charcoal-dextran stripped calf serum, seeded into 24-well plates (5Ч104 cells/well) and transfected with 0.5 μg ERE-Luciferase, 0.05 μg full-length hERα or hERβ and the internal control pCMV-β-gal (0.05 μg). In transfection assays with U2OS cells, cells were co-transfected with 0.3 μg pCMX-hSRC3 or pCMX empty vector (for experiments that did not require SRC3 expression) in addition to the expression plasmids used for HEC-1 cells. At 6 h post-transfection, cells were treated with increasing concentrations of rac-DPN, R-DPN and S-DPN or 17β-E2, and 24 h later cells were harvested and assayed for luciferase and β-galactosidase activities.