Ovarian stimulation with GnRH agonist, but not GnRH antagonist, partially restores the expression of endometrial integrin beta3 and leukaemia-inhibitory factor and improves uterine receptivity in mice.
BACKGROUND
The impact of different ovarian stimulation (OS) protocols on endometrial receptivity remains controversial. In this study, the effects of different OS on the expression of endometrial integrin beta3 subunit and leukaemia-inhibitory factor (LIF) during the implantation window and the implantation rate in mice were investigated.


METHODS
Three OS protocols were used, involving either pregnant mare's serum gonadotrophin (PMSG) alone, PMSG plus GnRH agonist or PMSG plus GnRH antagonist. Uterus samples were collected at 48 h after OS or ovulation and were detected with immunohistochemistry, Western blot and RT-PCR analyses. Normal embryos at gestation day 4 were transferred into the uteri of mice in the control and OS groups.


RESULTS
All OS groups showed a significant decrease in the expression of both the endometrial integrin beta3 subunit and LIF during the implantation window and the implantation rate. Among the three OS groups, GnRH agonist-treated mice showed a higher endometrial integrin beta3 subunit and LIF expression and a higher implantation rate. No significant difference was found in the measured indices between the GnRH antagonist and PMSG groups.


CONCLUSIONS
OS may inhibit the expression of endometrial integrin beta3 subunit and LIF and impair endometrial receptivity in mice. OS with GnRH agonist, but not GnRH antagonist, may partially restore the endometrial physiological secretion and improve uterine receptivity.
Ruan
Heng-Chao
HC
Department of Reproductive Endocrinology, Women's Hospital, School of Medicine, Zhejiang University, Hangzhou, Zhejiang, China.
Zhu
Xiao-Ming
XM
Luo
Qiong
Q
Liu
Ai-Xia
AX
Qian
Yu-Li
YL
Zhou
Cai-Yun
CY
Jin
Fan
F
Huang
He-Feng
HF
Sheng
Jian-Zhong
JZ
D000818:Animals; D001755:Blastocyst / Q000187:drug effects / Q000502:physiology; D004622:Embryo, Mammalian / Q000502:physiology; D004717:Endometrium / Q000166:cytology / Q000187:drug effects / Q000502:physiology*; D005260:Female; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists* / Q000037:antagonists & inhibitors*; D006064:Gonadotropins, Equine / Q000494:pharmacology*; D007150:Immunohistochemistry; D039661:Integrin beta3 / Q000187:drug effects / Q000235:genetics*; D015850:Interleukin-6 / Q000235:genetics*; D053605:Leukemia Inhibitory Factor; D051379:Mice; D008815:Mice, Inbred Strains; D009028:Morula / Q000187:drug effects / Q000502:physiology; D010062:Ovulation Induction / Q000379:methods*; D011247:Pregnancy; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017329:Triptorelin Pamoate / Q000494:pharmacology*; D014599:Uterus / Q000166:cytology / Q000187:drug effects / Q000502:physiology*
D006064:Gonadotropins, Equine; D039661:Integrin beta3; D015850:Interleukin-6; D053605:Leukemia Inhibitory Factor; C507838:Lif protein, mouse; D017329:Triptorelin Pamoate; D007987:Gonadotropin-Releasing Hormone