On the role of epididymal factors in sperm fertility

Abstract

Notwithstanding our improved descriptive knowledge of events occurring to mammalian sperm during epididymal maturation, the nature of the mechanisms involved in the development of such primary functions as forward motility (Bedford, 1975) and zona pellucida recognition (Saling, 1982) remain obscure.This review attempts to summarize the latest information produced by our laboratory in relation to the interaction of epididymal products with spermatozoa and the bearing that this interaction might have on sperm function.Our interest has been primarily focused on androgen-induced secretory epididymal proteins that associate to sperm during epididymal transit and that our group has described in rats (Cameo and Blaquier, 1976), hamsters (Gonzalez Echeverria, Cuasnic6 and Blaquier, 1982) and humans (Tezón et al., 1985b).Immature hamster sperm, obtained from the proximal segments of the epididymis, were used as a model to induce in vitro modifications of their functions (Cuasnicu et al., 1984a). Exposure of these spermatozoa to a preparation enriched with androgen-induced secretory proteins EP2-EP3 (Gonzalez Echeverria, was able to induce a significant increase in homologous zona pellucida binding (Cuasnicu et al., 1984b). Since zona binding seemed to be one of the functions developed by sperm during epididymal transit (Cuasnic6 et al., 1984a;Saling, 1982), our results were interpreted as reflecting the in vitro advancement of the maturational stage of these spermatozoa which was caused by the added epididymal preparation. Similarly, we were also able to show that immature sperm gained in fertilizing ability when pre-treated in vitro with the epididymal extract prior to in vivo or in vitro insemination (Gonzalez Echeverria et al., 1984).Our latest results confirm these preliminary findings and support the role of epididymal proteins in sperm maturation. Briefly, our studies show that the preparation of the epididymal proteins mentioned above, in which EP2-EP3 represented 16 % of the total protein, had a biological activity such that, on the average, treated sperm fertilized twice as many oocytes as their untreated controls (Gonzalez Echeverria et al., 1984 (Gwatkin, 1977)

Bovine spermatozoa react to in vitro heat stress by activating the mitogen-activated protein kinase 14 signalling pathway

“…It is believed that the functionality of spermatozoa is largely dependent on the post-translational modifications of proteins in the absence of de novo protein synthesis. This occurs during epididymal maturation and post-ejaculatory capacitation of spermatozoa in the female reproductive tract (Blaquier et al 1988a(Blaquier et al , 1988b. The main function of a spermatozoon is to travel through the female genital tract, traverse the zona pellucida of an oocyte and finally deliver the male haploid genome to the oocyte during fertilisation.…”

Identification of SRC as a key PKA-stimulated tyrosine kinase involved in the capacitation-associated hyperactivation of murine spermatozoa

“…Intriguingly, the acquisition of functional competence during capacitation occurs in the complete (Engel et al, 1973;Hernandez-Perez et al, 1983) or virtual (Gur and Breitbart, 2006) absence of gene transcription and translation. Thus, whereas incubation of human, mouse, rat and bovine spermatozoa with radiolabeled amino acids has recently revealed evidence of limited protein synthesis in these cells, the general consensus is that the acquisition of functionality during capacitation is largely dependent on posttranslational modifications to pre-existing proteins (Blaquier et al, 1988a;Blaquier et al, 1988b;Ross et al, 1990).…”

Histochemical localization of zinc ions in the epididymis of the rat

“…In mammals, the epididymis is known to play an important part in the maturation of sperm cells and their ability to fertilize eggs (Bedford, 1967;Orgebin-Crist, 1967;Glover & Nicander, 1971; and reviews by Cooper, 1986Cooper, , 1990Robaire & Hermo, 1988;Blaquier et al, 1988Blaquier et al, , 1989. However, some authors have suggested that the human sperm cells do not have to be present in and traverse the epididymis in order to attain motility and develop into mature cells (Adler & Makris, 1951;Silber 1980Silber , 1989a.…”