Calcium, magnesium, and zinc contents in organelles of prostatic origin in human seminal plasma

Human seminal plasma contains organelles (granules and vesicles) of prostatic origin. A Mg²⁺- and Ca2⁺-dependent ATPase activity, associated with the membranes of the organelles, was determined and related to the contents of calcium, magnesium and zinc in the granules. The samples were obtained from total ejaculates of 42 men. Fourteen had normal spermiograms. Sperm-free, post-vasectomy ejaculates were obtained in 12 cases. In 16 other men, 9 had sperm concentrations less than 40 x 10⁶/ml and 7 had asthenospermia and/or teratozoospermia. No statistically significant intergroup differences were found when the organelle contents of the metals were determined with flameless atomic absorption spectroscopy. In fractionated ejaculate specimens, the distribution of the metals was correlated to the organelles rather than to the amorphous substance also present in ejaculate. In comparison with the surrounding seminal plasma, an unambiguous enrichment of metals as obtained in the organelles. It is suggested that the organelles exert a regulatory function on spermatozoa by modulating in their microenvironment the concentration of divalent cations necessary for the spermatozoan motility.