Expression of cyclooxygenase-1 and -2 in ovine endometrium during the estrous cycle and early pregnancy.
In this study we investigated the expression of the two cyclooxygenases, cox-1 and -2, in sheep uterine tissues during the estrous cycle and early pregnancy. We identified the cox-2 isoform in the ovine uterus by Western blot and demonstrated that the two cyclooxygenases exhibited different patterns of expression. Cox-1 was expressed at steady state levels in the endometrium during the estrous cycle and comparable stages of pregnancy. In contrast, cox-2 was highly and transiently expressed from days 12-15 of the estrous cycle and declined thereafter to undetectable levels. Endometrium from early pregnant ewes showed a similar pattern of cox-2 expression, although there was a slower decrease beyond day 15. Immunohistochemical studies demonstrated that cox-1 was localized in both epithelial and stromal cells, whereas cox-2 was localized solely in the luminal epithelium and to a lesser extent in the superficial glands. Treatment of ovariectomized ewes with steroids indicated that expression of cox-1 remained at constant levels whatever the treatment. In contrast, endometrial cox-2 was highly induced by a 10-day progesterone treatment. Estradiol slightly increased cox-2 expression but only after progesterone priming. Collectively these results suggest that the developing ability of the uterus to synthesize PGs is due to the induction of cox-2.
Charpigny
G
G
Laboratoire de Physiologie Animale, Institut National de la Recherche Agronomique, Jouy-en-Josas, France. gch@jouy.inra.fr
Reinaud
P
P
Tamby
J P
JP
Créminon
C
C
Martal
J
J
Maclouf
J
J
Guillomot
M
M
D000818:Animals; D015153:Blotting, Western; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D015237:Dinoprost / Q000378:metabolism; D004717:Endometrium / Q000201:enzymology*; D004958:Estradiol / Q000494:pharmacology; D004971:Estrus / Q000502:physiology*; D005260:Female; D007150:Immunohistochemistry; D007527:Isoenzymes / Q000032:analysis / Q000378:metabolism*; D010052:Ovariectomy; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000378:metabolism*; D011374:Progesterone / Q000494:pharmacology; D011451:Prostaglandin-Endoperoxide Synthases / Q000032:analysis / Q000378:metabolism*; D012756:Sheep
D007527:Isoenzymes; D011374:Progesterone; D004958:Estradiol; D015237:Dinoprost; D051545:Cyclooxygenase 1; D051546:Cyclooxygenase 2; D011451:Prostaglandin-Endoperoxide Synthases