Direct evidence for formation of hybrid vesicles by fusion of plasma and outer acrosomal membranes during the acrosome reaction in boar spermatozoa.

A variety of treatment procedures was utilized to identify the origin and composition of the vesicles formed during the acrosome reaction of boar spermatozoa. Whether the acrosome reaction occurred spontaneously or was induced chemically the vesicles were hybrid vesicles composed of roughly equal proportions of plasma and outer acrosomal membranes.