The special extract of Rheum rhaponticum (ERr 731®) does not stimulate uterine growth and proliferation in ovariectomized wistar rats

The special extract ERr 731® from the roots of Rheum rhaponticum L. is the major constituent of Phyto-Strol which has been used for the relief of menopausal symptoms for decades. We recently demonstrated the nearly pure estrogen receptor-β (ERβ) agonistic properties of ERr 731® in human endometrial and bone cell systems. Here we present investigations on the effects of ERr 731® on uterine growth and proliferation in ovariectomized (OvEx) rats following subcutaneous treatment for 72h with the therapeutic dose of ERr 731® (0.1mg/kg body weight (bw)/day), a pharmacological dosage range of 1–100mg/kg bw/d or with th…