Examination of the effects of melatonin on embryo viability and development in freezing mouse embryos

The aim of this thesis is to investigate the effects of melatonin addition on embryo culture medium in vitro development after freezing mouse embryos by solid surface vitrification (SSV). It is known that melatonin supports oocyte maturation and embryo development. The purpose of this study is to investigate the in vitro growth and quality of melatonin-supplemented culture medium after freezing the eight-cell mouse embryos by solid surface vitrification. For this purpose, B6CBAF1 mice were superovulated with 10 IU PMSG and intra-peritoneal (IP) injection of 10 IU hCG after 48 hours to obtain embryos in the pronuclear stage (PN) embryos. Afterwards, they were incubated up to eight The aim of the thesis study cell steps under the conditions of 37°C and 5% CO₂ in KSOM medium + 4mg BSA medium. Eight-cell embryos were kept frozen in solid surface vitrification method (SSV) by first keeping them 12 minutes at 37°C in the equilibration solution (then washing them in freezing solution) and then dropping them to aluminum surface in liquid nitrogen with in 20 seconds. Embryos obtained after distillation were incubated in KSOM + 4mg BSA medium to 37°Cand 5% CO₂ to blastocyst stage. A total of three groups were used in the experiment: control, SSV group and SSV + 10 ¯¹² M melatonin. Number of embryos used were 35, 74 and 70 respectively. The growth rates of in vitro development were 97,14%, 86,49% and 92,86%, respectively. According to differential staining total cell counts were 64, 48 and 33 respectively. According to the results obtained; this study demonstrates the first time that melatonin supports in vitro development of embryos frozen by SSV vitrification.