Sperm-specific phospholipase C zeta (PLCζ) initiates intracellular calcium (Ca2+) transients which drive a series of concurrent events collectively termed oocyte activation. Numerous investigations have linked abrogation and absence/reduction PLCζ with forms male infertility in humans where activation fails. However, very few studies examined potential relationships between advancing age, both ...

It is well established that in addition to generating the diploid state in the zygote, the sperm also endows the oocyte with paternal centrioles, proteins and RNAs. Although the exact roles of mRNA introduced into the oocyte by the sperm are not completely understood. However, literature background, suggested that RNAs may have a vital role in embryo cleavage and further development. Therefore,...

The early events of fertilization that precede and cause activation of an egg have not been fully elucidated. The earliest electrophysiological change in the sea urchin egg is a sperm-evoked increase of the egg's membrane conductance. The resulting depolarization facilitates entry of the fertilizing sperm and precludes the entry of supernumerary sperm. The sequence of the increase in the egg's ...

In human fertilization, the sperm centrosome nucleates a radial array of microtubules called the sperm aster. The sperm aster is responsible for apposition of male and female pronuclei, and later gives rise to the first meiotic spindle. The objective of this study was to determine microtubule assembly and chromatin configuration in rabbit oocytes following intracytoplasmic injection with human ...

Abstract Sperm handling procedures and its usage for in vitro fertilization are crucial standardized experimental operations on evaluation of reproductive performance, gamete quality, optimization protocols. In our study, the changes perch sperm motility parameters within 6-h chilled storage using 4 different activating solutions were compared. Eight sperm-to-egg ratio was also compared during ...

Changes in sperm features during the movement phase are especially interesting to study in external fertilization species whose sperm duration movement is long because this implies a significant adaptation of moving cells to the external medium. This study describes the changes in tetraploid Pacific oyster sperm characteristics in relation to time post activation. Sperm individually collected o...

The aim of this report has been evaluating protamine content and DNA integrity of two patients with globozoospermia undergoing Intra Cytoplasmic Sperm Injection (ICSI). Semen analysis was carried out according to WHO criteria. Protamine deficiency and DNA fragmentation was assessed using Chromomycin A3 and sperm chromatin dispersion assay respectively. ICSI and chemical activation were carried ...

Background: Herbal plants often contain active pharmacological compounds they are commonly used for the treatment and prevention of different diseases. Objectives The present study was aimed to identify the effects of different concentrationsof Erucasativa extraction (ESE) on human sperm motility for infertile male in vitro. Methods: Thirty five semen samples were obtained from men (mean age 27...

Oocytes inseminated by intracytoplasmic sperm injection using fresh ejaculated or freeze-dried rhesus macaque sperm showed similar activation, sperm aster assembly, and male-female pronuclear apposition rates.

Cannabinoids and endocannabinoids negatively influence sperm functions. These substances have been demonstrated in many mammalian tissues, including male and female reproductive tracts, and previous studies have shown the presence of functional receptors for cannabinoids in human sperm. The present study, by means of RT-PCR and Western blot techniques, demonstrates that human sperm express the ...