Effects of progesterone on nuclear ribonucleoprotein constituents of endometrial cells of the rat.
The effects of changes of progesterone concentration on 3H-uridine incorporation and on the volume or number of nuclear ribonucleoprotein particles of the rat endometrial epithelial cells are studied in vivo and in vitro. All progesterone treatments are carried out after estradiol priming and their results are compared with estradiol-treated controls sampled from the same uterus or the same pool of isolated cells. Progesterone induces the same changes, in the parameters studied, administered in vivo or in vitro. Nuclear volume undergoes small but significant increases between 1/2 and 8 h of treatment. The total number of extranucleolar ribonucleoprotein structures as well as the incorporation of 3H-uridine on non-nucleolar areas are also increased by progesterone treatments. However, the numerical density of perichromatin granules does not change during these experiments. The nucleolar volume and the incorporation of 3H-uridine in this structure are increased after an early diminution. These results indicate that progesterone induces small increases in the rate of transcription in the nucleolus and in non-nucleolar genes. The constancy of the density of perichromatin granules suggests that progesterone, in contrast to estradiol, does not affect the ratio transcription/transportation of RNA to the cytoplasm.
D000818:Animals; D002466:Cell Nucleolus / Q000378:metabolism; D002467:Cell Nucleus / Q000187:drug effects / Q000378:metabolism*; D004717:Endometrium / Q000166:cytology / Q000378:metabolism*; D005260:Female; D066298:In Vitro Techniques; D011374:Progesterone / Q000494:pharmacology*; D051381:Rats; D012261:Ribonucleoproteins / Q000378:metabolism*; D014316:Tritium; D014529:Uridine / Q000378:metabolism
D012261:Ribonucleoproteins; D014316:Tritium; D011374:Progesterone; D014529:Uridine