[Role of macrophages in mouse uterine during the peri-implantation period].

OBJECTIVE: To investigate the effect of macrophages on embryo implantation by observing the distribution of macrophages in mouse uterine tissues during the peri-implantation period. METHODS: Uterine tissues were collected from pregnant (n=30) and pseudopregnant mice (n=30) during the peri-implantation period. The distributions of macrophages, iNOS and leukemia inhibitory factor (LIF) were determined by immunohistochemistry and the correlations of macrophages with iNOS and LIF were analyzed. RESULTS: Macrophages were located mainly in the endometrium before D4.5 in the pregnant rats with D0.5 defined as the morning when a vaginal plug was observed. After D4.5, the macrophages was significantly reduced in number (P<0.05) in the endometrium and gradually migrated to the perimetrium. In the psudopregnant mice, macrophages were located mainly in the endometrium. Before D4.5, iNOS-positive cells were detected mainly in the endometrium and the myometrium in the pregnant rats and became significantly reduced on D4.5 (P<0.05); in the pseudopregnant mice, the positive cells were mostly detected in the endometrium. Significant differences were found in the distribution of the macrophages and LIF between the implantation and non-implantation sites (P=0.013). LIF was mostly located in the endometrium in the pregnant mice but scarcely detected in the pseudopregnant mice. CONCLUSION: Macrophages are located mainly in the endometrium and the implantation site where iNOS and LIF are expressed, suggesting the important role of macrophages in the determination of implantation.

Relationship between macrophages in mouse uteri and angiogenesis in endometrium during the peri-implantation period.

The objective of this study is to examine the change in macrophage numbers, inducible form of NO synthase (iNOS), and vascular endothelial growth factor (VEGF) expression both before and after embryo implantation in the uterine tissue of mice. In order to explore the mechanism of macrophages in endometrial angiogenesis, 8-week-old female mice were divided into three groups: pregnant group, pseudopregnant group (mated to male mice that had been vasectomized), and estrous group (unmated). Individuals from these three groups were sacrificed at time intervals D1.5 to D6.5. Formalin-fixed paraffin-embedded tissue was used for immunocytochemical localization of Mφ, iNOS, and VEGF utilizing standard methodology. The proportion of macrophages in the peripheral blood was determined by flow cytometry, and the relationship between macrophage, iNOS, and VEGF expression was analyzed. The proportion of peripheral blood macrophages in the pregnancy group was significantly higher than that in the other groups. The results of immunohistochemistry determined that the macrophages exhibited changes in both numbers and distribution. The number of macrophages in the endometrium of the pregnancy and pseudopregnancy groups was significantly higher than that in the control (estrous) group. In the pregnancy group, macrophage numbers dramatically decreased and gradually transferred to the perimetrium on D4.5. Immunostaining revealed strong staining in the pregnancy group and weaker staining in the pseudopregnant and control groups for both iNOS and VEGF. There was strong, dense immunostaining at the implantation site for both iNOS and VEGF, whereas light immunostaining was seen in interimplantation tissues on D5.5 to D6.5. In the pregnant group, peripheral blood and uterine macrophage proportions were negatively correlated, whereas the amount of macrophages, iNOS, and VEGF expression in the endometrium were positively correlated. The expression of iNOS and VEGF in the endometrium also displayed a strong positive correlation. In conclusion, during embryo implantation, macrophages levels decreased in the uterus, whereas the number of peripheral macrophages increased, suggesting that macrophages may migrate into the peripheral blood and uterus to adapt for pregnancy. Additionally, an increase in the expression of iNOS and VEGF was observed during the implantation window, implying that iNOS and VEGF may play an important role in promoting embryo implantation. The positive correlation between macrophages, iNOS, and VEGF in the implanting uterus implied that macrophages might regulate iNOS and VEGF during the implantation process.

[Effect of basal serum luteinizing hormone and luteinizing hormone/follicle-stimulating hormone ratio on outcomes of in vitro fertilization-embryo transfer in patients with polycystic ovarian syndrome].

OBJECTIVE: To evaluate the effect of basal serum luteinizing hormone (LH) and luteinizing hormone/follicle-stimulating hormone (LH/FSH) ratio on the clinical outcomes of in vitro fertilization-embryo transfer (IVF-ET) in patients with polycystic ovary syndrome (PCOS). METHODS: A retrospective analysis was performed of 134 IVF cycles in patients with PCOS. The cycles were classified into 2 groups according to serum levels of LH and also into 2 groups according to LH/FSH ratio, namely group A1 (LH≤10 IU/L), group A2 (LH>10 IU/L), group B1 (LH/FSH ratio<2), and group B2 (LH/FSH ratio≥2). The clinical characteristics, embryological data and pregnancy outcomes were compared between the groups. RESULTS: Patients in group A2 showed significantly higher FSH, T level, and LH/FSH ratio with a greater number of oocytes retrieved than those in group A1, but the time for down-regulation, duration of stimulation, AFC, LH and LH/FSH on the first day of stimulation, embryological data and pregnancy outcomes did not differ significantly between the two groups. Compared with group B1, group B2 showed higher basal LH, E2 level on the day of HCG, more oocytes retrieved and lower dose of gonadotropins used, but the time for down-regulation, duration of stimulation, LH and LH/FSH on the first day of stimulation and pregnancy outcomes were comparable between the two groups. CONCLUSION: A high basal LH level or a high LH/FSH ratio does not produce obvious deleterious effect on the clinical outcomes of IVF-ET in women with PCOS who take oral contraceptives for pretreatment before long GnRH-agonist protocol.