The cryopreservation effect on expression of EGF and EGFR genes in mouse during two-cell and blastocyst stages.

Nowadays, vitrification is used for the protection of surplus embryos in Assisted Reproductive Technologies (ART).However the genetically changed of cryopreserved (frozen-thawed) embryos is exactly unclear. This study was designed in order to evaluate of cryopreservation effect on expression of epidermal growth factor (EGF) and EGF-receptor genes in mouse during 2-cell and balstocysts stages.To stimulate the ovulation in mice, HCG was injected. After 44-46 and 86-88hours, 2-cells and blastocysts were collected, respectively. These embryos were divided into case and control groups. 2-cellsand blastocysts of control group were immediately stored in nitrogen tank for future studies. 2-cells and blastocysts of casegroup were cryopreserved using cryotop and after 2-4 mounts were thawed. The mRNA levels of EGF and EGF-R in mouse embryo during two-cell and blastocysts stages were quantified by reverse transcriptase (RT)-PCR in fresh and frozenthawed mouse embryo. Quantitative RT-PCR demonstrated a 2.1 fold reduction in EGF and a 1.8 fold reduction in EGFR in frozen-thawed two-cell stages compared with fresh two-cells. In mouse blastocysts, the RT-PCR analysis showed a 2.5l and1.6 fold reduction in EGF and EGFR mRNA levels respectively in frozen-thawed embryo compared with fresh one. Inconclusion, cryopreservation weakly alter the expression of EGF and EGF-R in mouse embryo during two-cell and balstocysts stages.

کلیدواژه ها:

EGF ، EGFR ، two-cell ، blastocyst ، Vitrification