THE SYNTHESIS OF DNA AND RNA IN NORMAL HUMAN ENDOMETRIUM IN SHORT-TERM INCUBATION IN VITRO AND ITS RESPONSE TO OESTRADIOL AND PROGESTERONE

Abstract

SUMMARY A method is described for short-term incubations in vitro of normal endometrium for the study of nucleic acid synthesis. Tissue suspensions of specimens obtained at curettage were incubated with and without hormones in a medium consisting of Parker's 199 medium and 20% adult human serum; [3H]thymidine and [14C]uridine were added. The isotope uptake into the nucleic acids was determined and related to the total amount of DNA in each sample. Marked variation in DNA synthesis was noted in endometria obtained at different phases of the menstrual cycle. RNA synthesis varied less. After the addition of progesterone, synthesis of both nucleic acids was reduced. The magnitude of this response varied in different endometria. Thus DNA synthesis in endometria already under strong progesterone influence in vivo (midsecretory phase) was least affected when progesterone was added in vitro.