[Estrogen and progesterone interactions on the estrogen receptor and thymidine kinase in the immature rat uterus].
In medical clinics or experiments, progesterone (P) has been used for treatment of adenomatous hyperplasia or cancer of the endometrium. In the present paper, effects of P in combination with or without estradiol-17 beta (E2) on the estrogen receptor (ER) and thymidine kinase (TK) activity in immature rat uterus are described. P has been reported to interfere with the replenishment of the cytoplasmic ER of the rat uterus. In the present study, no translocation of the cytoplasmic ER to the nucleus was found after the injection of P, whereas P slightly enhanced the wet weight and the TK activity of the uterus. The TK activity increased 20 to 30 times the control level at 30 hours after the injection of E2. However, the enzyme activity induced by E2 was inhibited by P which was approximately 1,000-fold or more dose of E2. This enzyme was separated into isozymes by DEAE-cellulose column chromatography. Induction of the specific TK isozyme, which was induced by E2 in immature rat uterus and closely related to DNA synthesis, was found to be inhibited by P.
D000818:Animals; D004247:DNA / Q000096:biosynthesis; D004347:Drug Interactions; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D011374:Progesterone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D011960:Receptors, Estrogen / Q000187:drug effects / Q000378:metabolism*; D013937:Thymidine Kinase / Q000378:metabolism*; D014599:Uterus / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*
D004967:Estrogens; D011960:Receptors, Estrogen; D011374:Progesterone; D004247:DNA; D013937:Thymidine Kinase