[Chronological changes in sex steroids and prostaglandins receptor concentrations in rat endometrium during peri-implantation period].
Successful completion of implantation requires coordinated functional synchronism of fertilized egg and endometrium. In the present study, these synchronized changes were analyzed by chronological changes in estradiol (E2), progesterone (P4) and prostaglandin E2 and F2 alpha (PGE2, PGF2 alpha) receptor (R) concentrations in various sites in rat endometrium during the peri-implantation period. Unilaterally pregnant horn prepared by tubal ligation was also used. The results obtained: Nuclear E2R (E2RN) increased in the first 5 days of the fertilized cycle but decreased after that in the pregnant horn. P4RN, on the other hand, continued to increase throughout the period studied. PGE2-R remained low until the 6th day but thereafter showed a rapid increase. PGF2 alpha-R was significantly higher in the pregnant horn but showed a fall after day 6. Cyclooxygenase distribution, studied by 14C-indomethacin binding, showed an increase in the peri-implantation period. The synchronous changes required for successful implantation, therefore, involve complex changes in steroids as well as the prostaglandin receptor concentration in the endometrium around the implantation tissue.
Takahashi
T
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Department of Obstetrics and Gynecology, Nihon University School of Medicine, Tokyo.
D000818:Animals; D002467:Cell Nucleus / Q000378:metabolism; D010064:Embryo Implantation; D047108:Embryonic Development; D004717:Endometrium / Q000201:enzymology / Q000378:metabolism*; D005260:Female; D011247:Pregnancy; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011959:Receptors, Estradiol / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*; D011982:Receptors, Prostaglandin / Q000378:metabolism*; D018078:Receptors, Prostaglandin E
D011959:Receptors, Estradiol; D011980:Receptors, Progesterone; D011982:Receptors, Prostaglandin; D018078:Receptors, Prostaglandin E; C034671:prostaglandin F2alpha receptor; D011451:Prostaglandin-Endoperoxide Synthases