Reversible inhibition of nuclear chromatin decondensation (NCD) ability of human spermatozoa induced by prostatic fluid

Abstract

In semen from donors with adequate secretory function of the prostate, spermatozoa in the 1st (prostatic) portion of the ejaculate were more resistant to nuclear swelling in sodium dodecyl sulfate (SDS) than spermatozoa from the 2nd (vesicular) portion. No such difference was revealed by a donor with severely impaired prostatic function. This demonstrates that some sperm nuclear chromatin stabilizing factor(s) is present in normal prostatic fluid. The chromatin stabilizing factor(s) could largely be removed by washing the spermatozoa in saline containing albumin. Spermatozoa sensitized to SDS in this manner regained their SDS resistance upon exposure to normal (Zn rich) prostatic fluid. Such exposure induced a high degree of resistance in natively SDS sensitive spermatozoa. Zn of prostatic or other origin may reversibly inhibit a nuclear chromatin decondensation ability (NCD-ability). Such a mechanism may be of essential importance for male genome transfer.