OBJECTIVE Artificial oocyte activation (AOA) is an effective method to avoid total fertilization failure in human in vitro fertilization-embryo transfer (IVF-ET) cycles. AOA performed using a calcium ionophore can induce calcium oscillation in oocytes and initiate the fertilization process. We evaluated the usefulness of AOA with a calcium ionophore in cases of total fertilization failure in pr...

Nickel damages the male reproductive system. We investigated beneficial effects of silibinin which has metal-chelating and antioxidant properties over nickel toxicity. Both antioxidative in testes overall related to sperm motility, membrane acrosome integrity orally administered Silibinin were evaluated against harmful 30 day intraperitoneal sulfate (5 mg/kg/day) administration rats. Male rats ...

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...

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...

Background: During spermatogenesis the sperm nucleus exchange histones against cystein rich protamines, which stabilize the sperm chromatin and protects the DNA against damages. At ejaculation the age of the patient, handling routines, processing of the semen sample and the storage of the final sperm suspension might damage the DNA. Sperm chromatin stability and DNA damages are evaluated with d...

Fertilization depends on cell surface recognition proteins that interact and thereby mediate binding and subsequent fusion of the sperm and egg. Overlapping complementary DNA's encoding the egg plasma membrane receptor for sperm from the sea urchin Strongylocentrotus purpuratus were cloned and sequenced. Analysis of the deduced primary structure suggests that the receptor is a transmembrane pro...

Background Failure of Male Pronucleus (MPN) formation is a major concern in the success of Intracytoplasmic Sperm Injection (ICSI) in some species. Despite the conducted unsuccessful efforts to improve ICSI efficiency in ovine, the present study was aimed to improve MPN formation and embryo development in ovine ICSI procedure through accompaniment of sperm pretreatment with co-injection of some...

Capacitation encompasses the molecular changes sperm undergo to fertilize an oocyte, some of which are postulated to occur via a cAMP-PRKACA (protein kinase A)-mediated pathway. Due to the recent discovery of cAMP-activated guanine nucleotide exchange factors RAPGEF3 and RAPGEF4, we sought to investigate the separate roles of PRKACA and RAPGEF3/RAPGEF4 in modulating capacitation and acrosomal e...