Ability to activate oocytes and chromosome integrity of mouse spermatozoa preserved in EGTA Tris-HCl buffered solution supplemented with antioxidants

authorPotential methods for cryopreservation of mouse spermatozoa are freeze-drying, desiccation, and suspension in EGTA Tris–HCl buffered solution (ETBS: 50 mM NaCl, 50 mM EGTA, and 10 mM Tris–HCl). To determine the duration that mouse spermatozoa suspended in ETBS-based solutions could retain their normal characteristics without freezing, spermatozoa collected from the cauda epididymis were suspended in ETBS or in ETBS supplemented with the antioxidants, dimethyl sulfoxide (DMSO), or _DL-α-tocopherol acetate (Vitamin E acetate; VEA) diluted in DMSO, then held at ambient temperature (22–24 °C) for up to 9 days. When oocytes were injected with spermatozoa preserved in ETBS alone, activation rates of oocytes and chromosome integrity at the first cleavage metaphase decreased at 1 day (P<0.001) and 2–4 days (P