OBJECTIVE To study the potential protective action in vitro of oviductal epithelial cell membrane proteins against oxidative damage in human spermatozoa. DESIGN Prospective in vitro study. SETTING University research laboratory and infertility clinic. PATIENT(S) Semen from men attending the infertility clinic at the Queen Mary Hospital with normal semen parameters (World Health Organizati...

We evaluated the ability of immature pig oocytes (at germinal vesicle stage) to detect differences in the in vitro penetration rates of boar spermatozoa. In Experiment 1, immature and ovulated oocytes (n=303) were exposed to capacitated boar spermatozoa to determine if the penetrability of immature pig oocytes was comparable to that of ovulated oocytes. The percentages of penetrated oocytes and...

Heat stress has long been recognised as a cause of subfertility in farm animals. The objectives of the present study were to elucidate the effect of heat stress on sperm function and involvement of the mitogen-activated protein kinase (MAPK) 14 signalling pathway. Spermatozoa incubated for 4 h at a physiological temperature (38.5°C) exhibited significantly (P<0.05) reduced motility, plasma memb...

Induction of human sperm chemotaxis is an established phenomenon, though signaling systems physiologically involved have not been identified. Recently, it has been demonstrated that RANTES is present in the follicular fluid and that this molecule is a chemoactractant for human spermatozoa. However, the presence of beta-chemokine receptors on human spermatozoa has never been reported. By cytomet...

Aminopeptidase N (APN/CD13) and neutral endopeptidase (NEP/CD10) are enzymes present in human sperm cells and involved in regulation of sperm motility of noncapacitated spermatozoa. We investigated the involvement of APN/CD13 and NEP/CD10 in motility and in kinematic parameters of human capacitated spermatozoa. Sperm cells isolated by a discontinuous Percoll gradient (40%-80%) followed up by sw...

this study investigated the concentration/time dependent effects of nanosilver colloid on the motionparameters of the ejaculated ram spermatozoa in vitro. after incubation of sperm samples for 30, 60, 120 and 180 min in the presence of nanosilver colloid (0, 0.001, 0.01, 0.1, 1 and 10 ppm), the motion parameters were evaluated by computer assisted sperm analysis. there was a significant (p

The selection of morphologically normal spermatozoa is critical to obtain high breeding performances in boar breeding farms and artificial insemination (AI) centers. Parameters for the selection of semen mainly include total sperm motility, concentration, and morphology. However, these primary parameters are often not reliable for discriminating between normal and abnormal, non-fertilizable spe...

background: the lipids of the spermatozoa membrane are important for the fluidity and flexibility of spermatozoa. however, spermatozoa’s lipids are the main substrates for peroxidation, which may provoke severe functional disorder of sperm. objective: the aim of this study was to investigate the fatty acids composition of spermatozoa in men with asthenozoospermia, asthenoteratozoospermia and ol...

Choline is a crucial factor in the regulation of sperm membrane structure and fluidity, and this nutrient plays an important role in the maturation and fertilizing capacity of spermatozoa. Transcripts of phosphatidylethanolamine N-methyltransferase (PEMT) and choline dehydrogenase (CHDH), two basic enzymes of choline metabolism, have been observed in the human testis, demonstrating their gene e...

The use of cryopreserved donor spermatozoa for insemination has become necessary to decrease the risk from sexually transmitted infectious diseases. Lower fecundity rates have been reported with this practice. Efforts have been applied to increase success, including identification of those sperm characteristics which correlate with increased fecundity. Data from in-vitro fertilization have reve...