BACKGROUND The aim of this study was to investigate the in vitro effects of the Fusarium fungus-derived mycotoxin, zearalenone and its derivatives alpha-zearalenol and beta-zearalenol on motility parameters and the acrosome reaction of stallion sperm. Since the toxic effects of zearalenone and its derivatives are thought to result from their structural similarity to 17beta-estradiol, 17beta-est...

This study investigates the effect of supplementing bovine follicular fluids (FF) to rabbit sperm motility, acrosome reaction and transaminases activities. Ovarian FF were collected from 46 pairs of bovine ovaries. Normal follicles were classified, according to their diameters, into small (SFF, ≤4 mm), medium (MFF,>4-8 mm), large (LFF,> 8 mm) and cystic (CSTFF,>20 mm). Rabbit semen was collecte...

Our previous studies showed that gamma-aminobutyric acid (GABA)A and GABAB receptors are involved in rat sperm acrosome reaction induced by progesterone or GABA. Here, we report the presence of GABAC receptor in rat testis and spermatozoa. Full-length complementary DNA encoding the rho1, rho2 and rho3 subunits of GABAC receptor were cloned from rat testis; their sequences are identical to those...

We report for the first time that phospholipase D activity in sea urchin spermatozoa can be regulated by a component of egg jelly known to induce an acrosome reaction. The fucose-sulfate glycoconjugate (FSG) of egg jelly that induces an acrosome reaction in spermatozoa caused Ca2+-dependent increases in 1,2-diacylglycerol and phosphatidic acid. Diacylglycerol concentrations were increased 2-fol...

The objective of the present study was to investigate the effects of the direct addition of pentoxifylline (PF) to the ejaculates of men with poor sperm quality before freezing on post-thaw sperm motility, viability, acrosome integrity, and agonist-induced acrosome reaction. Semen specimens from 16 infertile men with impaired sperm count and motility (oligoasthenozoospermia) were divided into t...

Cryopreservation causes extensive damage to spermatozoa, thereby impairing their fertilizing ability. The purpose of this study was to determine if the direct addition of pentoxifylline to the seminal plasma before cryopreservation improved sperm motility and acrosome reaction. Semen specimens from 15 healthy volunteers were divided into two aliquots. One aliquot was treated by adding 5 mM pent...

Capacitation (modifications required for gamete fusion) is produced by incubating guinea-pig spermatozoa in vitro in a chemically defined medium. It is shown that during such incubation a net uptake of Ca2+ by the sperm occurs in two distinguishable phases. An initial loose association of Ca2+, possibly to surface sites, is unaffected by agents (Mg2+, inhibitors of mitochondiral function) that ...

To fertilize eggs, mammalian sperm must first undergo a form of cellular exocytosis called the acrosome reaction. In 1983, my laboratory reported that nanomolar concentrations of ZP3, one of three zona pellucida glycoproteins from mouse eggs, induced mouse sperm to undergo the acrosome reaction in vitro. Seven years later, this article from Florman’s laboratory (O’Toole et al., 2000) revealed t...

Calcium flux is required for the mammalian sperm acrosome reaction, an exocytotic event triggered by egg binding, which results in a dramatic rise in sperm intracellular calcium. Calcium-dependent membrane fusion results in the release of enzymes that facilitate sperm penetration through the zona pellucida during fertilization. We have characterized inositol 1,4,5-trisphosphate (IP3)-gated calc...