Electrophoretic patterns of spermatozoal nucleoproteins (NP) in fertile men and infertility patients and comparison with NP of somatic cells

Abstract

During spermatogenesis in mammals the evolutionary early histones are replaced step by step by more species specific nucleoproteins (protamines). The protamines protect the genetic information of the male against mutagenic or other damaging influences and possibly play a role in male fertility. A method was presented to study the nucleoproteins (NP) of single human ejaculates. This procedure was checked concerning its usability and validity by bull spermatozoa. The NP of cryopreserved human spermatozoa of fertile men and of infertility patients were investigated and compared with the electrophoretic patterns of NP of somatic hepatocytes of rat and mouse. A total of 48 semen samples were studied. Ten of these samples were obtained from semen donors of proven fertility and 38 samples were collected from male partners of infertile couples. Photodensitometrically it could be distinguished between percentages of non-protamines (PNP) and percentages of protamines (PP). The PP varied intra-individually with a mean standard deviation of 34%, analogously to the alterations of classical semen parameters. The PP of fertile men did not significantly differ from the infertility patients with normal spermiogram parameters but showed a significantly higher value compared with the semen samples with pathological spermiograms. On average the PP of all infertile patients were significantly lower than the PP of fertile semen donors.