No abstract

No abstract

No abstract

Epididymal and ejaculated rabbit sperm and ejaculated human sperm were incubated at pH 7.0 and pH 9.0 to test for phosphatase activity. With the substrates tested, ATP, ADP, AMP, ITP, p-nitro-phenyl phosphate, and glucose-&phosphate, enzymes capable of dephosphorylating ATP at pH 7.0 were localized on the periacrosomal portion of the plasmalemma i n epididymal but not in ejaculated sperm. The enzyme was active without divalent cations. In both epididymal and ejaculated sperm the outer membrane of the acrosome was reactive at pH 9.0 with ATP and Ca++. These strikingly different properties of the phosphatases on the plasmalemma and acrosome membrane indicate

No abstract