Tyrosine nitration is a widely used marker of peroxynitrite (ONOO-) produced from the reaction of nitric oxide (NO.) with superoxide (O2(.-)). Since human spermatozoa are able to produce both NO. and O2(.-) during capacitation in vitro, we investigated whether spontaneous tyrosine nitration of proteins occurs in human spermatozoa and evaluated the physiological effects of peroxynitrite on sperm...

G12 monoclonal antibody (mAb), one of a library of constructed mAb directed against human sperm proteins, was found by immunoperoxidase staining to label the post-acrosomal and neck regions of fixed human cauda epididymal and ejaculated spermatozoa. Epithelium and fluid of caput epididymis were strongly labelled while there was no staining on testis and efferent ducts. Western lot analysis reve...

In mice and humans, a normal offspring can be obtained by injecting a single spermatozoon into an oocyte, the process called intracytoplasmic sperm injection (ICSI). When three or more mouse spermatozoa with intact acrosomes were injected into individual mouse oocytes, an increasing proportion of oocytes became deformed and lysed. Oocytes did not deform and lyse when acrosome-less spermatozoa w...

PURPOSE Sperm immobilization factor isolated from Staphylococcus aureus immobilizes human spermatozoa as well as motile bacteria, showing that sperm immobilization factor receptor might be shared by bacteria and human spermatozoa. Thus, we sought to identify a common sperm immobilization factor binding receptor on spermatozoa and bacteria. MATERIALS AND METHODS Sperm immobilization factor was...

BACKGROUND Despite interest in cryopreservation of individual or small number of human spermatozoa, to date, little data is available as regards its effectiveness. We systematically reviewed the outcome after cryopreservation of individual or small numbers of human spermatozoa in patients with severe male factor of infertility. METHODS We searched the MEDLINE, EMBASE, Cochrane Systematic Revi...

Leptin is secreted mainly by fat, which is involved in energy metabolism and reproduction. Leptin and itsreceptor (Ob-R) have been detected in human spermatozoa and testis, thus it can be concluded leptin involves in male physiology. The goal of this study was determination of the presence of leptin receptor mRNA in the ram testis, epididymis and spermatozoa by reverse transcription polymerase ...

Testis-specific proteins, synthesized during spermatogenesis and spermiogenesis, are necessary for spermatid differentiation and/or for mature sperm function during fertilization. However, majority of these genes have neither been identified nor fully characterized. Testis developmental related gene 1 (TDRG1), a newly identified human testis-specific gene, encodes a 100-amino-acid protein witho...

The sperm acrosome reaction takes place in response to progesterone and zona pellucida. Progesterone may act on more than one type of surface receptor, of which one is a gamma-aminobutyric acid (GABA) type A-like receptor. Although there is direct evidence of GABA initiation of mouse sperm acrosome reaction, there are conflicting results regarding GABA-induced exocytosis in human spermatozoa. W...

Nitric oxide is a chemical messenger which functions as a neurotransmitter or as a cytotoxic agent. Nitric oxide synthase (NOS) has been isolated from various mammalian reproductive tissues. The presence or absence of NOS in spermatozoa has not yet been reported. We therefore tested human and murine spermatozoa for NOS activity by measuring the conversion of arginine to citrulline. No activity ...

BACKGROUND Sperm protein 17 (Sp17) is a three-domain protein that contains: 1) a highly conserved N-terminal domain that is 45% identical to the human type II alpha regulatory subunit (RII alpha) of protein kinase A (PKA); 2) a central sulphated carbohydrate-binding domain; and 3) a C-terminal Ca++/calmodulin (CaM) binding domain. Although Sp17 was originally discovered and characterized in spe...