[Effects of estrogen progesterone on endometrial glycocalyx expression in superovulated mice in the implantation window time]

It has been reported that apical glycocalyx expression of uterine affects embryo implantation. The aim of this study was to determine endometrial glycocalyx and endometrial thickness after estrogen and progesterone injection in hyperstimulated mice at luteal phase. Adult male and female mice were used for induction of pesudopregnancy. The mice were divided into two groups experimental and control groups. Female mice in the experimental group were superovulated and were then mated with vasectomised mice to induce psudopregnancy Experimental group based on hormone injection was subdivided into five groups 1] Estrogen, 2] Progesterone, 3] Estrogen + Progesterone, 4] Antiprogesterone + Estrogen, 5] Sham. Pesudopregnancy in the control group was achieved without any hyperstimulation. The uterines of all groups were collected after 4.5 days of pregnancy and prepared for the assessment of endometrial thickness and endometrial glycocalyx expression. The results showed that estrogen and progesterone injection increased the intensity of PAS reaction, whereas progesterone decreased this. Also our results showed that the endometrial thickness in the sham group was the highest and in the progesterone group was the lowest Our results showed that addition of estrogen to progesterone, compared to P supplementation alone, provided appropriate endometrial conditions to embryo implantation. Hence combination of estrogen and progesterone injection as luteal support hormones can be used in IVF protocols

[Effects of different doses of LIF on IVM rate and cumulus expansion in mouse oocytes]

The aim of this research was to study the effects of different doses of LIF on GVBD and MII development rate and cumulus expansion. Immature mice superovulated with HMG and GV oocytes obtained from ovary 48 hours later. The GV oocytes were cultured in TCM199 with 100, 500 and 1000 RI /ml LIF. Cumulus expansions were evaluated with two examiners and numbers of MII oocytes were recorded. For denuding the oocytes hyaloronidase was used. Our results showed that the rate of GVBD and MII development increased in -groups with LIF compared with control group. Rate of MII development with 1000 IU/ml LIF was significantly higher than that of control group [P<0.05]. Cumulus expansion in group with 1000 IU/ml LIF improved significantly compared with control group [p<0.05]. Our results showed that LIF could improve IVM rate in dose dependant. Also cumulus expansion improved in group with LIF and increased oocyte quality

[ effects of Matrigel on the developmental processes of mouse blastocysts]

Culturing embryos on Matrigel[TM], is one of the most suitable methods for studying in vitro embryonic developments. As Matrigel has not been used extensively in different species for embryonic development studies, this study was undertaken to determine the effects of Matrigel on the developmental processes of mouse blastocysts. To a number of female NMRI mice, hMG and HCG injections were made for ovulatory stimulation and then they mated with males from the same strain. Later on, blastocysts were obtained and randomly divided into 2 groups: 150 case blastocysts and 134 control blastocysts. Blastocysts were cultured for 48 hours in M16 medium, supplemented with 4mg/ml of bovine serum albumin [BSA]. Later, the blastocysts were compared with the blastocysts cultured in Matrigel plus the same medium. Developmental studies were carried out every 24 hours for 2 days. The data was analyzed by SPSS software and the results were tested by chi-squared. After 24 hours, a significantly higher ratio of embryos reached the hatched blastocysts stage ? in the case group [74%], compared with that of the control group [52.2%], [p<0.05]. At the same time the percentage of fragmented blastocysts in the control group was 11.9% which was significantly higher than the case group [2%], [p<0.05]. After 48 hours, 41% of blastocysts cultured in the control medium, developed to stage I, the value being significantly more than the blastocysts in the case group [p<0.05]. Moreover, after the same period of time [48 hours], the percentage of stage II hatched blastocysts in the case group [79%] was higher than the control groups [59%], [p<0.05]. Matrigel use in enriched culture media can increase development and growth of mouse blastocysts. It also seems that ultrastructural studies of cultured embryos or immunocytochemical studies from this regard would be beneficial in understanding the processes involved

[Effect of vitrification on apoptosis in mouse blastocysts]

In recent years there have been a great advances in vitrification of embryos. However, there is no reliable vitrification protocol to ensure a high embryo survival rate, Because the mechanisms of embryo injury has not been discovered precisely. The aim of the present study was to determine the effects of vitrification on apoptosis in mouse blastocysts. Ninety five mouse blastocysts were obtained by flushing from Swiss Albino mouse and randomly divided into control and experimental groups. Blastocysts in the control group [52] were cultured in Ml6 media for 2 hours and then the apoptotic index were obtained after staining by TUNEL technique with PI. Blastocysts in the experimental group [43] were vitrified just after flushing in EFS40 solution and kept in LN2 for one month. After thawing and culture in M16 for 2 hours, the apoptotic indices were obtained by TUNEL staining. The results showed that the mean number of blastomers in the vitrified blastocysts group [44.91 +/- 2.47] was not significantly different [P=0.176] from those that seen in the control group [50.23 +/- 2.9], while the mean number of apoptotic blastomers in vitrified blastocysts group [4.08 +/- 0.28] was significantly higher [P=0.02] as compared to the control group [4.93 +/- 0.22]. The mean apoptosis Index in vitrified blastocysts [11.87 +/- 0.63] was significantly higher [P<0.004] than the control group [9.12 +/- 0.67]. We can conclude that the vitrification can increase apoptotic cell death in mouse blastocysts

effect of progesterone after ovarian hyperstimulation on the ultrastructure of mouse endometrium during preimplantation period

The aim of this study was to investigate the morphological and ultrastructural changes of mouse endometrium by daily injection of progesterone, after ovarian hyperstimulation during preimplantation period. Material and NMRI mice, 6-10 weeks old, were initially hyperstimulated using hMG and hCG injection and then daily progesterone injection was performed subcutaneously [1 mg/mouse], thereafter they were mated artificially. 3.5 days after hyperstimulation, the animals were killed by cervical dislocation and the samples were obtained from 13 middle part of uterine horns. Specimens were also obtained from naturally and artifically impregnated control groups. The samples were devided and processed for light [H and E, PAS] and electron microscopic studies. Our results indicated that, daily injection of progesterone after hyperstimulation decreased the height of the epithelium. In the experimental group several fat droplets were seen in the basal part of epithelium. Also intercellular spaces were decreased decidualization was not seen. Results show that daily injection of progesterone after hyperstimulation altered the ultrastructure of endometrial epithelium which resulted in inhibition of decidualization reaction and can affect the uterine receptivity during implantation

Morphological study of mouse [BALB/c] thymus after high and low dose dexamethasone treatment

Dexamethasone induces thymic atrophy and thymocyte apoptosis. In the present study histological and ultrastructural changes which occur in the thymus of the mouse [BALB/c] following treatment with high [20 mg/kg] and low [8 mg/kg] doses of dexamethasone were investigated. In low dose treated mice, apoptotic cells were observed focally and localized mainly in thymic nurse cells [T.N.C.]. A zone of intact thymocytes was formed in the medulla of animals receiving 20 mg/kg of dexamethasone as well as an increase in trans-endothelial vesicles and a decrease in the size of the vesicles in the cortical capillaries. The enveloped thymocytes within thymic nurse cells respond to dexamethasone through apoptosis, and these changes were seen to be more severe in mice treated with high doses of dexamethasone. The formation of apoptotic cells in the thymus caused by low dose dexamethasone mimics the physiological process of cell death. Differential effects of low dose and high dose dexamethasone may have pharmacological and immunological implications