MACAQUE SPERM FUSION WITH ZONA-FREE HAMSTER OOCYTES

Semen from six cynomolgus macaques was washed twice by centrifugation in BWW media and resuspended in 1:2 (vol:vol) of Tes-Tris-buffered egg yolk extract (EXT) diluent and BWW (EXT-BWW). Caffeine and dbcAMP were added to induce capacitation. Sperm were treated with calcium ionopho re, A23187, followed by the addition of EXT to recover motility, then washed into BWW. The percent motile sperm was similar in ionophore-tre ated and control sperm suspensions, but motility of treated sperm decr eased significantly by 20 min after treatment. The percentage of viabl e, acrosome-reacted sperm was 56.3% following ionophore treatment vers us 4.0% in control suspensions. When ionophore-treated sperm were coin cubated with zona-free hamster oocytes, 51% of oocytes had evidence of sperm fusion and no oocytes were penetrated after incubation with con trol sperm. These results are consistent with the hypothesis that maca que sperm are capable of fusion with zona-free hamster oocytes if sper m are viable and acrosome-reacted.