Selenium, rubidium and zinc in human semen and semen fractions.

The levels of selenium, rubidium and zinc were determined in samples of semen, seminal plasma and spermatozoa from men with suspected infertility, together with several parameters of semen quality. The proportion of whole semen selenium present in sperm increased with increasing sperm count from 0 to 40%. For rubidium 98 +/- 4% and for zinc 95 +/- 8% of the total amount in semen was contained in seminal plasma. In seminal plasma a positive correlation was found between the levels of zinc and selenium, and between the levels of zinc and rubidium, indicating that, like zinc, selenium and rubidium in seminal plasma also derive mainly from the prostate gland. Semen quality parameters, such as sperm motility, vitality, speed and morphology, were not correlated with the contents of the three elements in either whole semen or seminal plasma. As the seminal content of selenium is dependent on the proportion of prostatic secretion in seminal plasma and on the sperm count, and both factors can vary considerably, the selenium level of whole semen does not appear to be a suitable parameter for investigation of the relationship between selenium and semen quality. Provisional measurements suggest lower sperm selenium levels at abnormally low or high sperm counts.