Effect of mifepristone on uterine receptivity in guinea pigs.
OBJECTIVE
To determine the effect of a low-dose mifepristone regimen on endometrial receptivity in guinea pigs.


METHODS
Histologic evaluation for endometrial staging and immunoreactivity of cytokines [leukemia inhibitory factor (LIF) and interleukin-6 (IL-6)] were preformed on fixed endometrial tissue, and relative abundance of endometrial estrogen (E), and progesterone (P) receptor mRNA were evaluated with semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) in which cyclophilin mRNA, a housekeeping gene product, was co-amplified as the reference standard.


RESULTS
Mifepristone at 0.03 mg.kg-1 . d-1 induced a delay in endometrial maturation. The staining intensity of LIF and IL-6 decreased in treated guinea pigs. E and P receptor mRNA increased significantly and uterine stage delayed in treated guinea pigs.


CONCLUSIONS
Mifepristone at 0.03 mg.kg-1 . d-1 delayed development of endometrium. This study provides further evidence that endometrial maturation can be altered without affecting ovarian ovulatory function.
Liu
Cheng-Quan
CQ
National Laboratory of Contraceptives and Devices Research, Shanghai Institute of Planned Parenthood Research, Shanghai 200032, China. songsi@mail.sippr.stc.sh.cn
Wang
Zhong-Xing
ZX
Yuan
Yao
Y
D000818:Animals; D003280:Contraceptives, Oral, Synthetic / Q000494:pharmacology*; D004305:Dose-Response Relationship, Drug; D004717:Endometrium / Q000187:drug effects* / Q000254:growth & development / Q000378:metabolism; D005260:Female; D006131:Growth Inhibitors / Q000378:metabolism; D006168:Guinea Pigs; D015850:Interleukin-6 / Q000378:metabolism; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines / Q000378:metabolism; D015735:Mifepristone / Q000494:pharmacology*; D012333:RNA, Messenger / Q000378:metabolism; D011960:Receptors, Estrogen / Q000378:metabolism*; D011980:Receptors, Progesterone / Q000378:metabolism*
D003280:Contraceptives, Oral, Synthetic; D006131:Growth Inhibitors; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; D008222:Lymphokines; D012333:RNA, Messenger; D011960:Receptors, Estrogen; D011980:Receptors, Progesterone; D015735:Mifepristone