Progesterone in vitro stimulates secretion of a specific protein by ovine epithelial endometrial cells.
Cultured ovine epithelial endometrial cells from oestrogen-treated ovariectomized ewes were treated in vitro with combinations of oestradiol-17 beta (E), progesterone (P) and the P-receptor antagonist RU486 (each 10(-6) to 10(-9) M), in the presence of [35S]methionine. Neither DNA content of dishes nor total protein were increased in treatment compared with control dishes. Incorporation of [35S] into secreted protein was lower from cells treated in vitro with P or E + P (10(-9) M) than from those treated with E (10(-9) M, P less than 0.01). Incorporation of [35S] into cellular protein was decreased by P (10(-9) M, P less than 0.025). SDS-PAGE analysis of secreted proteins enabled measurement of levels of a 46K protein which is secreted maximally following E + P administration in vivo. In vitro, P either alone or with E (each 10(-7) M) increased the abundance of the 46K protein in cell secretions by a factor of 1.5 +/- 0.1 (N = 9) or 1.8 +/- 0.3 (N = 10) respectively (P less than 0.01) compared with controls. The administration of E (10(-7) M) or either or both steroids at 10(-9) M, was without effect. RU486 alone (10(-6) to 10(-8) M) was also without effect but in the presence of E + P or P, blocked the increase in the 46K protein, suggesting this effect is mediated via binding of P to its receptor.
Salamonsen
L A
LA
Medical Research Centre, Prince Henry's Hospital, Melbourne, Victoria, Australia.
Healy
D L
DL
Findlay
J K
JK
D000818:Animals; D002478:Cells, Cultured; D004717:Endometrium / Q000187:drug effects / Q000378:metabolism*; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D004958:Estradiol / Q000494:pharmacology*; D004963:Estrenes / Q000494:pharmacology; D005260:Female; D015735:Mifepristone; D010052:Ovariectomy; D011374:Progesterone / Q000494:pharmacology*; D014176:Protein Biosynthesis; D011506:Proteins / Q000302:isolation & purification / Q000378:metabolism; D012756:Sheep
D004963:Estrenes; D011506:Proteins; D015735:Mifepristone; D011374:Progesterone; D004958:Estradiol