Transcript Analysis of Heat Shock Protein 72 in Vitrified 2-Cell Mouse Embryos and Subsequent in Vitro Development

Objective: the aim of the study was to compare the effects of two different concentrationsofcryoprotectantsbycryotopvitrificationonsurvival,developmentalcapacityandheatshock protein 72 (hsp72) expression of two-cell mouse embryos. materials and methods: in this experimental study, transcript analysis of hsp72 genewas performed on non-vitrified and vitrified 2-cell mouse embryos via a nested quantitativepolymerase chain reaction (nqpcr) subsequent to normalization with hprt1 as thereference gene. the different cryoprotectant combinations were 15% (vit1:7.5% of eachethylene glycol (eg) and dimethyl sulfoxide (dmso), 30% (vit2:15% eg + 15% dmso)and control group with no cryoprotectants. vitrified and fresh 2-cell embryos were culturedto obtain cleavage and blastocyst formation rates. the results were analyzed via one-wayanalysis of variance and the mean values were compared with least significant difference(lsd) (p < 0.05). results: the relative expression of hsp72 in vit2 (30% v/v) was significantly higher thanvit1 (15% v/v). survival rates were the same for both vitrification treatments and significantlylowerthanthecontrolgroup.cleavageandblastocystratesinvit1 were significantlyhigher than vit2 while those in two vitrified groups were significantly lower than the controlgroup. conclusion: our developmental data demonstrated that vit1 treatment (7.5% eg and7.5% dmso) was more efficient than vit2 (15% eg and 15% dmso) in mouse embryos.the cryotopvitrification with two concentrations of cryoprotectants caused the relativechanges of hsp72 transcript level, but the stability of the gene in vit1was significantlyhigher than vit2 and closer to the fresh 2-cell embryos.