Prostaglandin modulation of mouse and human sperm capacitation

To determine whether prostaglandins produce a capacitation and/or acrosome reaction, the effect of prostaglandins on capacitated mouse spermatozoa and the effect of prostaglandin pre-incubation on human and mouse spermatozoa were studied. Prostaglandins did not induce an acrosome reaction in capacitated mouse sperm. PGE1 pre-incubation in a protein-free medium enhanced acrosome loss of mouse sperm challenged with A-23187 or solubilized mouse zona pellucida. Human sperm were pre-incubated in media containing prostaglandins, and an acrosome reaction was induced with calcium ionophore or human follicular fluid. PGE1 pre-incubation enhanced acrosome loss by human sperm when the action was induced with calcium ionophore, but had no effect on follicular fluid induction. We conclude that PGE1 acts as a capacitating factor in vitro for mouse spermatozoa, and enhances acrosome-reaction induction with calcium ionophore in human spermatozoa.