ABSTRACT
Aim To investigate the estrogenic activities of four components from pregnant mare’s urine extract. Methods The estrogenic activities of four components were assessed using two in vitro tests:the MCF-7 cell proliferation assay (E-screen test)and the luciferase transfected CHO cell gene reporter assay.In the lucifer-ase reporter gene assay,the reporter gene plasmids PGM-ERE-Luc and ERαor ERβand a control plasmid (pRL-cmv)were transiently co-transfected into CHO cells to establish an ERα-or ERβ-cell screening system which was used to measure estrogenic activity of four compounds.Results MCF-7 cells treated with HP, DHP,PT and HA significantly proliferated,thereby of-fering in vitro evidence for the estrogenic activities of HP,DHP,PT and HA,and they showed dose-depend-ent activities.Compared EC50 of PE and RPE with that of E2 ,HP,DHP,PT and HA exerted relatively weak estrogenic activities.The in vitro ER-mediated reporter gene assay revealed that HP,DHP,PT and HA dis-played estrogenic activities mediated by ERβor ERα. Compared with the EC50 of E2 ,HP,DHP,PT and HA exhibited lower estrogenic potencies.Conclusion HP, DHP,PT and HA possess weaker estrogenic activities than E2 .