Co-culture with somatic cells such as commercially vero cells (kidney cells of green African monkey) or primary culture of oviduct cells is a useful method to inhance in vitro development of mammalian preimplantation embryos. So, this study was initiated to investigate the effect of co-culture on development of mouse embryos with ampullary epithelial cells of hamster oviduct in two different complex media. Also, cleavage and ultrastrucutre of embryos in both co-culture and control were considerd.
Ampullary and isthmic epithelial cells of hamsters that administrated with human menopausal gonadotropins (HMG) and human chorionic gonadotropin (hCG) were isolated by collagenase treatment (0.25%) and cultured. The 2-cell NMRI mouse embryos were cultured for 4 days, with the cells in three different media [(DMEM/Ham's F12 and MEM?) supplemented with bovine serum albumin (BSA, 4mg/ml) or in control groups (each medium + 4mg/ml BSA)] and in T6 supplemented with fetal calf serum (FCS) with ampullary and isthmic cells or its control (T6+10% FCS). At 4th day, blastomeres of blastocysts were counted by Torkowshy's air drying method or fluorescence microscopy for cleavage rate consideration. Some of morulae and blastocysts were chosen for electron microscopy study.
Hatching blastocyst and blastocyst rate increased in co-culture groups of media in comparison with control groups (69% vs 28% in DMEM/Ham's F12, P<0.001, and 79% vs 53% in MEM?, P<0.001), 80% (ampulla) and 76% isthmus vs 53% in T6).