Effects of Different Chemical Activations on the Development of Mouse Parthenogenetic Embryos

In order to find out the suitable activation protocol for mouse oocytes, the cleavage and development of mouse oocytes activated by several different chemical activation protocols were investigated. Matured oocytes were grouped into 9 treatments randomly: (1) inomycin + 6-DMAP; (2) ionomycin + 6-DMAP+ cytochalasin B (CCB); (3) ionomycin+ cycloheximide (CHX); (4) ionomycin + CHX + CCB; (5) 7% ethanol + 6-DMAP; (6) 7% ethanol + 6-DMAP + CCB; (7) 7% ethanol + CHX; (8) 7% ethanol + CHX + CCB; (9) Sr2+ + CCB. The parthenogenetic efficiencies of these activation protocols on mouse oocytes, the optimum treatment duration and the age of oocytes activated by Sr2+ + CCB were analysed. The resultus indicated that the parthenogenetic efficiencies of mouse oocytes are related with activation protocols and the age of oocytes. Mouse oocytes can be activated effectively by ionomycin + 6-DMAP + cytochalasin B or Sr2+ + CCB, the rate of activated oocytes and the development rate of hatched blastocysts in these groups are higher than that in other treatment groups (P0.05). Sr2+ + CCB protocol is the best method of mouse oocyte activation. Mouse oocytes at 20h post hCG injection are the optimum stage for parthenogenetic activation by Sr2+ + CCB and 4h is the best treatment duration for Sr2+ + CCB activation. 6-DMAP is more effective than CHX in activating mouse oocytes.