Effect of progesterone injection on progesterone receptor levels and distribution in untreated and short-term Premarin-primed pre-menopausal and post-menopausal endometrium.
Cytosolic and nuclear progesterone receptors (RPC, RPN) were measured in post-menopausal endometria, using [3H]R5020 as the radioligand, and the findings compared with those in pre-menopausal endometria. Total RP levels (RPC + RPN) in post-menopausal endometria were low, i.e. less than 2000 fmol/mg DNA. A 7-11 day course of Premarin (conjugated equine oestrogen) treatment in post-menopausal subjects resulted in RP levels in 11818 +/- 3008 fmol/mg DNA, which were higher than those in proliferative, mid-cycle and Premarin-primed pre-menopausal endometria. Progesterone injection 1-3 h before tissue collection resulted in a change in the distribution of the RP in both premenopausal and post-menopausal Premarin-primed endometria and pre-menopausal proliferative and mid-cycle endometria. Following the progesterone injection RPN levels increased to 57 +/- 9% of the total as compared with 23 +/- 8% in endometrial samples from women who received no progesterone.
D000328:Adult; D002467:Cell Nucleus / Q000032:analysis; D003600:Cytosol / Q000032:analysis; D004717:Endometrium / Q000032:analysis* / Q000187:drug effects; D004966:Estrogens, Conjugated (USP) / Q000494:pharmacology*; D005260:Female; D006801:Humans; D008593:Menopause; D008875:Middle Aged; D011374:Progesterone / Q000494:pharmacology*; D011980:Receptors, Progesterone / Q000032:analysis*
D004966:Estrogens, Conjugated (USP); D011980:Receptors, Progesterone; D011374:Progesterone