While the function of the ubiquitous Na,K-ATPase alpha1 subunit has been well documented, the role of the sperm-specific alpha4 isoform of this ion transporter is less known. We have explored the importance of alpha4 in rat sperm physiology by taking advantage of the high sensitivity of this isoform for the inhibitor ouabain. Using concentrations that selectively block alpha4 activity, we found...

Cholesterol is a key molecule in the mammalian physiology of especial particular importance for the reproductive system as it is the common precursor for steroid hormone synthesis. Cholesterol is also a recognized modulator of sperm functions, not only at the level of gametogenesis. Cholesterol homeostasis regulation is crucial for posttesticular sperm maturation, and imbalanced cholesterol lev...

I argue that several unusual aspects of spider sexual biology make them extremely promising subjects for future research on sperm competition and cryptic female choice, and outline promising lines for future research. The important traits include: double, bilaterally symmetrical genitalia (allowing the use of the same animal as experimental and control and thus providing unusually complete cont...

Sperm flagellar motion is the outcome of a dynamic interplay between the axonemal cytoskeleton, the peri-axonemal accessory structures, and multiple regulatory networks that coordinate to produce flagellar beat and waveform. Tektins are conserved components of the flagellar proteome in evolutionarily diverse species and are believed to play essential roles in the mechanics of sperm motility. Us...

Upon ejaculation, mammalian spermatozoa have to undergo a sequence of physiological transformations within the female reproductive tract that will allow them to reach and fertilize the egg. These include initiation of motility, hyperactivation of motility and perhaps chemotaxis toward the egg, and culminate in the acrosome reaction that permits sperm to penetrate the protective vestments of the...

The reproductive physiology of the Pacific white-sided dolphin, Lagenorhynchus obliquidens, was characterized to facilitate the development of artificial insemination (AI) using cryopreserved spermatozoa. Specific objectives were to: 1) describe reproductive seasonality of the Pacific white sided dolphins; 2) describe urinary LH and ovarian steroid metabolites during the estrous cycle; 3) corre...

background: industrial copper ingest is a common form of poisoning in animals. zinc has an important role in the physiology of spermatozoa, in sperm production and viability. objective: this study was set to investigate whether the adverse effects of long term copper consumption on quality of rat spermatozoa could be prevented by zinc therapy. materials and methods: forty eight mature (6-8 week...

Motility parameters of the spermatozoa in most fish species spawning in fresh water like Rutilus kutum lasts for a short time after activation. Ovarian fluid significantly influenced sperm motility (motility duration period) and percent motility (progressive forward motile sperm). Both of these variables generally increased as the concentration of ovarian fluid increased from 33% to 50%, respec...

Monoclonal antibodies (mabs) have been used as a powerful tool for identification of newer sperm proteins. However, conventional hybridoma technology rarely provides chance to obtain mabs to epididymal proteins. To increase this chance, we have used an alternate method of neonatal tolerization. In this protocol, animals were tolerized at birth using testicular proteins followed by immunization ...