Background The role of calcium in physiological phenomenona such as sperm acrosome reaction and hyper-activation has been well known. Calcium ionophore A23187 is routinely used for induction of acrosome reaction in mammalians sperm. Therefore, we decided to evaluate the effect of calcium ionophore A23187 on the sperm hyper-active motility patterns. MaterialsAndMethods Ten semen samples from ind...

background: nanoparticles have wide range of application while there are some reports regarding their probable effects on male reproductive system and spermatozoa. objective:  the aim of this study was to evaluate the effect of different doses of silver nanoparticles (agnps) (70nm) on acrosome of rat spermatozoa and number of spermatogenic cells. materials and methods:  in this experimental stu...

The divalent metal cation ionophore A23187 rapidly induces a normal acrosome reaction in a population of guinea-pig sperm suspended in calcium medium. In the course of the acrosome reaction, proacrosin, the zymogen precursor of the protease acrosin, is activated. Although the acrosome reaction causes exocytosis of the acrosomal contents, 'soluble' acrosin is not released in significant amounts ...

In the fertilization process of sea stars, sperm is activated to go through the acrosome reaction before cell fusion. We focused on induction of the acrosome reaction as a key process in fertilization. Six species of sea stars were used in this study: Asterias amurensis, Asterias rubens, Asterias forbesi, Aphelasterias japonica, Distolasterias nipon, and Asterina pectinifera. Acrosome reaction ...

The divalent metal cation ionophore A23187 induces an acrosome reaction in guinea-pig sperm which is dependent on external calcium. Examination of this acrosome reaction by electron microscopy shows that it is morphologically normal. The known properties of A23187 and the morphological similarity between the acrosome reaction and the secretory discharges of other secretory cells suggests that t...

Zona pellucida (ZP)-induced acrosome reaction in sperm is a required step for mammalian fertilization. However, the precise mechanism of the acrosome reaction remains unclear. We previously reported that PLCdelta4 is involved in the ZP-induced acrosome reaction in mouse sperm. Here we have monitored Ca2+ responses in single sperm, and we report that the [Ca2+]i increase in response to ZP, which...

Gamete recognition in the mouse is mediated by galactosyltransferase (GalTase) on the sperm surface, which binds to its appropriate glycoside substrate in the egg zona pellucida (Lopez, L. C., E. M. Bayna, D. Litoff, N. L. Shaper, J. H. Shaper, and B. D. Shur, 1985, J. Cell Biol., 101:1501-1510). GalTase has been localized by indirect immunofluorescence to the dorsal surface of the anterior spe...

Platelet activating factor (PAF) is a novel signaling phospholipids that in addition to platelet activation has many biological properties. The acrosome reaction, as an essential step in mammalian fertilization, can occur in response to several agents such as PAF. Therefore, the present study aimed to assess the effect of PAF on the motility and acrosome reaction of ram spermatozoa. Semen was c...

OBJECTIVES Capacitation and acrosome reaction are prerequisites for fertilization. However, in vitro capacitation is not necessary for an agonist-induced acrosome reaction. We studied whether in vitro capacitation is important in spontaneous acrosome reaction and analyzed how capacitation before cryopreservation influences the acrosomal status of thawed spermatozoa. METHODS Semen specimens fr...

introduction: the acrosome is a sac shaped organelle contaning lysosomal enzyme that is located on the anterior of sperm head. during the acrosome reaction its content is released in the vicinity of the egg. the acrosome reacted sperm then penetrates through the egg barriers. there are several methods for evaluating the acrosomal status; some of those are complex, expensive and/or non-accurate ...