Binding of mammalian spermatozoa to the zona pellucida of homologous eggs is mediated by specific molecules on their surface membranes. In the present investigation we describe the biogenesis, epididymal processing and cellular distribution of a plasma membrane antigen (2B1) on rat spermatozoa that has a potential role in mediating zona binding. 2B1 is expressed postmeiotically in the testis as...

OBJECTIVE To study the effect of freeze-thaw on embryos derived from intracytoplasmic sperm injection (ICSI) using surgically retrieved and ejaculated spermatozoa. DESIGN Retrospective study. SETTING Private IVF center. PATIENT(S) Three hundred eighty-three patients undergoing frozen-thawed ET cycles. INTERVENTION(S) Testicular sperm aspiration (TESA) or percutaneous epididymal sperm as...

In mammals, posttesticular epididymal sperm maturation is considered an essential step in the transformation of immature testicular gametes to mature spermatozoa capable of fertilization. Reactive oxygen species (ROS) have been shown to be key actors in this maturation process, and it is now clear that ROS are central for sperm physiology in processes such as sperm maturation and capacitation. ...

When male Wistar rats were treated with aflatoxin B1, more than 50% of the spermatozoa were defective. Strangely, about 10% of these spermatozoa were embedded in a dense matrix. TEM observation revealed that a fairly high percentage of such spermatozoa had the outer membrane, mitochondrial sheath or fibrous sheath, depending upon the level along the sperm which was cut in the transverse section...

Spermatozoa are quite unique amongst cell types. Although produced in the testis, both nuclear gene transcription and translation are switched off once the pre-cursor round cell begins to elongate and differentiate into what is morphologically recognized as a spermatozoon. However, the spermatozoon is very immature, having no ability for motility or egg recognition. Both of these events occur o...

two experiments were designed to examine the effects of crude seminal plasma (csp) exposure ofejaculated and epididymal spermatozoa before freezing. experiment 1, two consecutive ejaculates werecollected (n=4) within 5 min, the second one was carried out in a tube containing fiser extender (coatedspermatozoa); by centrifugation, seminal plasma was removed from coated ejaculates. the pellets wer...

The lipids and proteins of sperm cells are highly regionalized in their lateral distribution. Fluorescence recovery after photobleaching studies of sperm membrane component lateral diffusibility have shown that the sperm plasma membrane is also highly regionalized in the extents and rates of diffusion of its surface components. These studies have also shown that regionalized changes in lateral ...

BACKGROUND The aim of our study was to review the results of microsurgically performed testicular sperm extraction (TESE) and to evaluate its possible long term effects on serum testosterone (T). METHODS We operated on 48 men (35 +/- 8 years) with non-obstructive azoospermia (NOA). If no spermatozoa were found following a micro epididymal sperm extraction (Silber et al., 1994) and testicular ...

E74 is a mouse monoclonal antibody raised against the acrosome-reacted guinea pig spermatozoa. This study describes immunolocalization of the E74 antigen in guinea pig spermatozoa. Immunoelectron microscopy of guinea pig spermatozoa shows that the E74 antigen is localized on the equatorial segment plasma membrane following the acrosome reaction but not associated with the surface of the acrosom...