In vitro Stimulation of Incorporation of Formate-¹⁴C in Surviving Uterine Segments by Hydroxylated Œstradiols

Abstract

RECENT studies in this laboratory have demonstrated that the incorporation of formate-¹⁴C into protein by surviving uterine segments is an early and sensitive indicator of œstrogen action (unpublished work with A. M. Herranen). Six hours after a single intravenous injection of 10 µgm. of œstradiol-17-β, the incorporation of formate in vitro by uterine horn segments is accelerated 250 per cent over the controls. The addition of the natural hormones directly to the in vitro incubation media has little or no effect on formate metabolism. In contrast, it is shown in this communication that the addition of the 2-hydroxy or 4-hydroxy derivatives of œstradiol to the reaction mixture results in a significant acceleration of the incorporation of format-¹⁴C into the proteins of the uterine segments.