The close connection of the acrosome of the animal sperm with the Golgi apparatus was first suggested by Bowen' in 1923, who stated that the acrosomal material might be "secreted" from the Golgi apparatus. While his cytological studies seem to support the concept that the acrosome is derived from the Golgi apparatus, the staining methods employed do not allow any conclusions as to the chemical ...

The aim of this study was to investigate whether a relationship exists between the presence of low numbers of leukocytes in normal ovulatory cervical mucus and sperm quality and lipid content after migration. The percentages of live, motile and morphologically normal spermatozoa, movement parameters assessed by computer-aided sperm analysis (CASA), and ionophore-induced acrosome reaction measur...

Evidence from pharmacological studies suggests that induction of the acrosome reaction of mammalian spermatozoa by solubilized zona pellucida, and possibly by progesterone, is dependent upon Ca2+ influx through voltage-operated Ca2+ channels. Studies on Ca2+ accumulation and membrane potential in ligand-stimulated or artificially depolarized spermatozoa support such a conclusion. Electrophysiol...

Mammalian sperm capacitation is an essential prerequisite to fertilization. Although progress is being made in understanding the physiology and biochemistry of capacitation, little has been yet explored about the potential role(s) of individual sperm cell protein during this process. Therefore elucidation of the role of different sperm proteins in the process of capacitation might be of great i...

Cryopreservation is an efficient way to store spermatozoa and plays a critical role in the livestock industry as well as in clinical practice. During cryopreservation, cryo-stress causes substantial damage to spermatozoa. In present study, the effects of cryo-stress at various cryopreservation steps, such as dilution / cooling, adding cryoprtectant, and freezing were studied in spermatozoa coll...

Syntaxins are membrane integrated Q-SNARE proteins known to participate in exocytosis. Vesicle docking involves the binding of two plasma membrane proteins, syntaxin and SNAP-25, to the vesicle membrane protein VAMP to form a stable trimeric core complex; synaptophysin is thought to regulate the formation of this complex. Although the members of Q-SNARE proteins are characterized in somatic cel...

There are several physiological and pharmacological evidences indicating that opening of voltage dependent Ca channels play a critical role in induction of acrosome reaction in mammalian sperm. We determined the intracellular free Ca concentration in ejaculated goat sperm using a fluorescent, Ca-specific probe, Fura2/AM, after the suspension of sperm in KRB medium, capable of sustaining capacit...

The ability of bovine follicular fluid (FF) and oviduct fluid (ODF) to capacitate sperm was determined. At concentrations of greater than 20%, both FF and ODF capacitated sperm within 4 hours, but at concentrations greater than 40%, FF also initiated the acrosome reaction. Non-luteal ODF at a concentration greater than 60% capacitated sperm within 2 hours. Non-luteal ODF maintained sperm motili...

One of the most important processes in fertilization is the fusion of egg and sperm; however, the molecular mechanisms involved in this process are not well understood. So far, using genetic approaches, only two proteins have been demonstrated to be necessary for this process: Izumo in sperm and CD9 in the egg. Here we demonstrate that sperm produced by Tssk6 (Sstk)-null mice present defects th...

The presence and role of c-ras proteins were investigated in mature human sperm cells. The v-H-ras monoclonal antibody (mAb) against the c-ras protein, p21, reacted specifically with the acrosomal region of methanol-fixed as well as unfixed-live capacitated and non-capacitated human sperm cell in the indirect immunofluorescence technique. The v-H-ras mAb predominantly recognized c-ras protein o...