The effects of ovarian steroids in controlling rat uterine prostaglandin F2-alpha during the peri-implantation period.
Rats with delayed implantation, induced by ovariectomy or hypophysectomy, as well as those with normal pregnancy were used to examine the changes in uterine prostaglandin F2 alpha (PGF2 alpha) associated with implantation. In normal pregnant rats, while maximal uterine production of PGF2 alpha was found at 09:00, maximal catabolic enzyme activity (CEA) was seen at 17:00 of day 4. Uterine content of PGF2 alpha was high at 17:00 of day 4, but decreased by 80% within the next 24 h. There was no change in PGF2 alpha production during the first 6 h after injection of estradiol to hypophysectomized animals. There was, however, a dramatic decrease in production within the next 6 h. In contrast, CEA was not different in animals treated with estrogen than in those receiving only progesterone. In ovariectomized animals, uterine PGF2 alpha production also was lowered by estrogen but in these animals CEA was significantly elevated 18 h after injection of estradiol. Estrogen caused a greater increase in PGF2 alpha content in the hypophysectomized, compared to the ovariectomized, rats. The results are consistent with the view that ovarian steroids play an important role in controlling the changes in uterine PGF2 alpha around the time of implantation in rat.
Kogo
H
H
Department of Pharmacology, Tokyo College of Pharmacy, Japan.
Ogawa
K
K
Takeo
S
S
D000818:Animals; D015237:Dinoprost / Q000096:biosynthesis*; D010064:Embryo Implantation / Q000187:drug effects*; D010065:Embryo Implantation, Delayed / Q000187:drug effects*; D004958:Estradiol / Q000494:pharmacology* / Q000502:physiology; D005260:Female; D007016:Hypophysectomy; D010052:Ovariectomy; D010053:Ovary / Q000502:physiology*; D010903:Pituitary Gland, Anterior / Q000502:physiology; D011247:Pregnancy; D011270:Pregnancy, Animal / Q000502:physiology*; D011374:Progesterone / Q000494:pharmacology* / Q000502:physiology; D051381:Rats; D011919:Rats, Inbred Strains; D014599:Uterus / Q000378:metabolism*
D011374:Progesterone; D004958:Estradiol; D015237:Dinoprost