Morphologic characteristics of the chemically induced acrosome reaction in human spermatozoa

The morphologic changes accompanying the acrosome reaction in human spermatozoa, as it is induced by the antibiotic A23187 and calcium ions, are described. The reaction is shown to be similar to that observed in other species when the reaction occurs spontaneously or is induced by physiologic fluids. The reaction in human spermatozoa differs from the chemically induced reaction in other species in that plasma membrane microfilaments, prominent in the boar, and tubular-like elements prominent in boar, rabbit, and monkey sperm, are not observed. Motility remains high when human spermatozoa are treated with A23187 and calcium and it is possible that these agents may be useful in the study of certain causes of infertility.