evidence supports the involvement of nitric oxide (no) in a varity of male reproductive processes such as spermatogenesis, spermiogenesis, sperm motion, sperm metabolism and sperm capacitation. however, low concentration of no is essential in biology and physiology of spermatozoa, but high amounts of no is toxic and has negative effects on sperm functions. on the other hand, it is established t...

There are few reports on the role of protein phosphatases during capacitation. Here, we report on the role of PP2B, PP1, and PP2A during human sperm capacitation. Motile sperm were resuspended in non-capacitating medium (NCM, Tyrode's medium, albumin- and bicarbonate-free) or in reconstituted medium (RCM, NCM plus 2.6% albumin/25 mM bicarbonate). The presence of the phosphatases was evaluated b...

OBJECTIVE To compare the sperm chromatin dispersion (SCD) test and the terminal uridine nick-end labeling (TUNEL) assay for assessment of sperm DNA damage. DESIGN Prospective comparative experimental study. SETTING Andrology laboratory. PATIENT(S) Twenty subfertile men with unexplained infertility. INTERVENTION(S) Sperm DNA damage was determined in the same semen samples using the TUNEL...

The ability of sperm cells to develop colored formazan by reduction of MTT was used earlier to develop a spectrophotometric assay to determine the viability of sperm cells for several mammalian species. It was the objective of the present study to visualize microscopically the location of the formazan in boar sperm cells. The MTT staining process of boar sperm cells can be divided into a series...

Electroejaculate traits and circulating follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone concentrations were analyzed in adult leopard cats (Felis bengalensis), a rare felid species indigenous to east Asia. The ability of leopard cat sperm to bind and penetrate zona-free hamster ova and zona-intact domestic cat oocytes in vitro was examined as a means of testing sp...

BACKGROUND Leptin and its receptor are present in spermatozoa; however, the role of leptin in sperm function is still controversial. Our present study aimed at demonstrating the effect of cryopreservation on sperm DNA fragmentation (DNAf) and investigating the possible effects of sperm capacitation techniques and leptin in vitro incubation on frozen-thawed sperm DNAf and oxidative stress. MET...

Most laboratory methods used to evaluate semen quality have not correlated highly with fertilizing capacity. The discovery of a variety of fluorochromes and compounds conjugated to fluorescent probes has enabled a more widespread analysis of sperm attributes, and in conjunction with the flow cytometer, permit the evaluation of a large number of spermatozoa. A number of characteristics of sperm ...

Spermatozoa vary enormously in their form and dimensions, both between and within species, yet how this variation translates into fertilizing efficiency is not known. Sperm swimming velocity is a key determinant of male fertilization success, but previous efforts to identity which sperm phenotypic traits are associated with swimming velocity have been unsuccessful. Here, we examine the relation...

This prospective study was performed to evaluate the relationship between interleukin-6 (IL-6), oxidative stress and sperm function following vasectomy reversal. We included 22 patients who underwent vasectomy reversal and 15 healthy sperm donors (controls) with normal sperm morphology criteria. Levels of IL-6 in the semen were measured by the enzyme-linked immunosorbent assay, and levels of re...

Sperm DNA damage has a negative impact on pregnancy rates following assisted reproduction treatment (ART). The aim of the present study was to examine the relationship between sperm DNA fragmentation and live-birth rates after IVF and intracytoplasmic sperm injection (ICSI). The alkaline Comet assay was employed to measure sperm DNA fragmentation in native semen and in spermatozoa following den...