Objective: To compare the uterine receptivity with different ovarian stimulation protocols, the endometrial expression of Integrin beta3 in mice's during the implantation window underwent different ovarian stimulation were studied.
Methods: Forty mice were randomly allocated into 4 groups of 10 mice. (1) GnRHant group, gonadotropin-releasing hormone antagonist (GnRHant) was given first for desensitizing the pituitary, then the pregnant mare's serum gonadotrophin (PMSG) was added for ovarian stimulation. (2) gonadotropin-releasing hormone agonist (GnRHa) group, GnRHa was given first for desensitizing the pituitary, then PMSG was added for ovarian stimulation. (3) PMSG group, injected with PMSG only; and (4) control group, given with saline of the same volume. Human chorionic gonadotropin (HCG) was injected to the mice of the GnRHant, GnRHa, and PMSG groups. Forty-eight hours after the mice of the control group the mice were killed. Their uteri were taken. RT-polymerase chain reaction (RT-PCR) was used to detect the expression of integrin beta3 mRNA. Immunohistochemistry (SP method) was used to locate and semiquantitatively measure the integrin beta3 in the endometrium during implantation window.
Results: (1) Immunohistochemistry: showed that the staining intensity of integrin beta3 was 3.74 +/- 0.15 in GnRHa group, 3.22 +/- 0.19 in the GnRHant group, and 3.24 +/- 0.18 in the PMSG group, all significantly lower than that in the control group (3.90 +/- 0.11, P = 0.023, 0.001, and 0.001). with a significant difference between the GnRHa group and the PMSG group (P = 0.001) and without a significant difference between the. GnRHant group and PMSG groups (P = 0.768). (2) RT-PCR showed that the relative quantity of integrin beta3 mRNA expression was 1.14 +/- 0.16 in the GnRHa group, 0.76 +/- 0.33 in the GnRHant group, and 0.73 +/- 0.26 in the PMSG group, all significantly lower than that in the control group (1.4 +/- 0.3, P = 0.045, 0.001, and 0.001). with a significant difference between the GnRHant and PMSG groups (P = 0.001) and without a significant difference between the GnRHant and PMSG groups (P = 0.857).
Conclusion: All of the ovarian stimulation protocols do harm to the mice's uterine receptivity. Ovarian stimulation combining GnRHa protocol in mice is better than PMSG alone protocol, because it can improve the uterine receptivity. Ovarian stimulation combining GnRHant protocol in mice decrease the uterine receptivity as well as the PMSG alone protocol.