Mammalian spermatids and spermatozoa express functional G protein-coupled receptors. However, bicarbonate-regulated soluble adenylyl cyclase (AC), the major AC present in these cells, is not directly coupled to G proteins. To understand how G protein-coupled receptors signal in spermatozoa, we investigated whether a conventional transmembrane cyclase is present and biologically active in these ...

In a previous study we showed that the administration of gossypol to rats for 34 days caused 2 types of modification of the epididymis: (1) the secretion of carnitine and inositol were reduced in the fluid, (2) the spermatozoa lost their motility and showed major morphological changes (head-flagella dissociation). We wished to clarify the early effects of gossypol on the epididymis. Sprague Daw...

In Vitro Fertilization (IVF) is the penetration of ovum cells by spermatozoa in a culture system and reproductive technique that useful for increasing efficiency sperm utilization. vitro fertilization applied to overcome problem infertility prevent birth defects. The success IVF influenced quality spermatozoa. order fulfill this, it necessary select spermatozoa, which separate good from total p...

Pre-selection of spermatozoa based on the relative DNA difference between X- and Y-chromosome bearing populations by flow cytometry is an established method that has been introduced into commercial cattle production. Although several important improvements have increased the sort efficiency, the fertilising ability of sexed spermatozoa based on offspring per insemination is still behind farmers...

BACKGROUND Spermatozoa with large vacuoles (SLV) may have a negative impact on embryo development. The origin of these vacuoles is unknown. We evaluated acrosome and nucleus alterations in isolated SLV, versus unselected spermatozoa. METHODS We studied 20 patients with teratozoospermia. Spermatozoa from the native semen sample and spermatozoa presenting a vacuole occupying >13.0% total head a...

Controlling the sex of offspring by the separation of X and Y chromosome-bearing spermatozoa using flow cytometry has been reported as a clinical technique aiding prevention of X-linked diseases. Although this technique has resulted in several hundred normal births in animals and at least one human birth, there is still concern over its genetic safety due to the involvement of two potentially m...

We investigated sperm nuclear vacuolation in relation to acrosome reactions and the maintenance of sperm motility. Thirty male patients who visited our Male Infertility Clinic were enrolled. These patients underwent conventional semen analyses, Acrobeads tests, and high-magnification observation of the sperm head to evaluate the degree of nuclear vacuolation on the Acrobeads test scoring after ...

During cryopreservation, spermatozoa are subjected to cryodamage that leads to a decline in fertilisation ability. Due to the complex nature of this process, the initial trigger for cryodamage remains unknown. Recently, we demonstrated that cryopreservation induces early apoptotic changes characterised by phosphatidylserine (PS) translocation via sterol loss from the plasma membrane of chicken ...

A fourfold increase in oxygen uptake by rabbit spermatozoa incubated in the rabbit uterus and a twofold increase in cock sperm¬ atozoa incubated in the hen's oviduct over ejaculated spermatozoa is the first reproducible biochemical change to be demonstrated in sperma¬ tozoa residing in the female genital tract. It was shown that these rapidly respiring spermatozoa were capacitated because they ...

fresh semen obtained from infertile men occasionally exhibits the total absence of motile sperm (100%asthenozoospermia). vitality tests may reveal that a proportion of the immotile sperm has functional membranes, which are considered viable. an easy test for the prior determination of sperm viability may assist in sperm selection for the microinjection of oocytes. the main objective of this stu...