Sperm capacitation by uterine fluid or beta-amylase in vitro.

Rabbit sperm developed the capacity to fertilize ova when incubated in utero or in vitro in fluids from estrous uteri. Incubation of sperm with beta-amylase in phosphate-buffered Locke's solution also resulted in capacitation. The data suggest that sperm capacitation involves enzymatic alteration of carbo-hydrate-containing seminal macromolecules which coat sperm and inhibit fertilization.