[Localization, on the head of ram spermatozoa, of affinity sites for the 64kD androgen dependent epididymal prealbumin].

The epididymis of the ram synthesizes under androgenic control of specific 64 kD protein. The purified protein appeared as a single band in SDS polyacrylamide gel electrophoresis. It was labelled and an antiserum was prepared in mice. Results showed localization of receptors sites for 64 kD on the periacrosomal plasma membrane of testicular spermatozoa. The protein itself was found on the periacrosomal area of both epididymal and ejaculated spermatozoa.