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Showing 1 to 18 of 18 for “"sperm function"”.
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Regulation of boar sperm function by the oviduct – formation of a sperm reservoir, modulation of Ca 2+ influx, and release from storage
… Upon insemination, a small fraction of the sperm deposited in the female reproductive tract is transported to the lower oviduct (isthmus) to form a functional sperm reservoir. The sperm reservoir extends sperm lifespan, prevents polyspermic fertilization, and is implicated in the regulation …
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The Sodium Pump Regulates Sperm and Sertoli Cell Function
Abnormalities in sperm function at the submicroscopic level (not detectable during routine semen evaluation) influence bull fertility and therefore the efficiency of cattle production. New knowledge regarding the molecular basis of spermatogenesis and sperm function will enable us to develop …
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Measurement of cyclic nucleotides in human sperm: experimental and clinical application
The biochemical state of human sperm is critical for fertilisation potential, yet no convenient or reliable methods are available to assess essential second messengers. Cyclic nucleotides (cAMP and cGMP) play a crucial role as signalling molecules for capacitation, motility, and acrosome reaction …
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Metabolism and cryo-sensitivity of domestic cat (Felis catus) and cheetah (Acinonyx jubatus) spermatozoa
<p> <p>Teratospermia (ejaculation of ≥ 60% structurally abnormal spermatozoa) is prevalent among felids facing extinction risk, including the cheetah. This trait also occurs in certain domestic cat populations, providing a valuable research model. Multiple components of sperm function are disrupted …
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Investigating the effect of phosphodiesterase inhibitors on human sperm motility and function
… male infertility. This may include problems with sperm concentration, motility and/or morphology. Sperm motility defects are associated with most cases of male infertility and provide problems for sperm reaching, binding to and penetrating the oocyte therefore impacting on fertilisation success. …
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Embryo and Gamete Development Upon Exposure to CCA Components: CrO3, CuO, and AS2O5
<p>Production of functional gametes and healthy embryos is essential for proliferation of all vertebrates, especially humans. Many compounds have toxic effects on developing gametes and embryos among which are chromium trioxide (CrO<sub>3</sub>), cupric oxide (CuO) and arsenic pentaoxide …
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Role of second generation phosphodiesterase inhibitors on mammalian sperm mobility
… and this is mostly characterised by reduced sperm motility (asthenozoospermia). Assisted Reproduction Technology (ART) is the only treatment option available for this condition. Over 20 years ago, non-selective phosphodiesterase inhibitors (PDEi), such as pentoxifylline, were shown to enhance …
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CatSper: Characterisation in Human Spermatozoa and Clinical Significance
Before a mature spermatozoon is able to fertilise the oocyte, it must first traverse the female reproductive tract, through obstacles such as highly viscous mucus. As the sperm is thought to be transcriptionally and translationally inactive, it must rely on cues from its external environment in …
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Investigation of spermatozoal metabolism and substrate utilization in domestic and non-domestic felids
Cryopreservation of spermatozoa is a critical aspect of assisted reproduction. However in most cases, this process causes diminished spermatozoal function and low cellular survival. The effects of cryopreservation are further compounded in spermatozoa from individuals with disorders known to affect …
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Identification of platelet activating factor (PAF) receptor in equine spermatozoa and its role in motility, capacitation and the acrosome reaction
… It may also serve as a biomarker for normal sperm function. The presence of PAF receptor on the spermatozoa of 10 stallions was investigated by immunofluorescence microscopy. Statistical analysis revealed that the fluorescence intensity, FI (Mean+/-SEM), in the post- acrosomal region (FI= …
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Zinc ion fluxes on the pathway to mammalian sperm fertilization competency
… the focus of understanding mechanisms leading to sperm fertilization competency and management of semen storage. Little focus has been placed on other divalent ions, including zinc ion (Zn2+). Further, the ultimate maturation event preparing mammalian spermatozoa for fertilization, sperm …
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Apoptotic markers in ejaculated human spermatozoa
The role of male germ cell death in spermatogenesis is an important one as it removes dysfunctional or genetically damaged germ cells and is necessary to maintain an optimal germ cell to Sertoli cell ratio. The formation of the bloodtestis barrier requires the elimination of excessive germ cells …
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Obesity-Induced Alterations in Sperm Quality, Testicular Morphology, and Extracellular Vesicle Localisation in Male Mice
… with decreased testosterone levels, impaired spermatogenesis and reduced sperm function. Extracellular vesicles (EVs), which facilitate cell-to-cell communication, have been discovered in various biological fluids. Specifically, in the male reproductive system, testicular-derived EVs have been …
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Curbing environmental pollution of water hyacinth by using it in drug discovery
… levels, and membrane integrity; (3) To evaluate functional changes in cancer cells' antioxidant stress response (ARE) promoter and tumour suppressor (p53 transcription activity) mechanisms, during extract treatment; and (4) Evaluate the effect of extracts and bioactive compounds on male fertility …
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Examining the (patho)physiology of physiologically relevant ligands present in the male and female reproductive tracts
… of the physiological regulation and function of the highly complex sperm cell. Understanding the critical roles of different proteins in maintaining sperm function is key to understanding the causes of sperm dysfunction. Currently, male infertility is clinically diagnosed by semen …
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Homologe intrauterine Insemination (IUI) im stimulierten Zyklus : Bedeutung von Spermiogrammparametern in Nativ-Spermiogrammen und nach Ejakulat-Aufbereitungen
… (BMI), for the fraction of local motil sperm in the basic spermiogram, for the percental change of the fraction of local motil sperm between the nativ and the processed spermiogram as well as for the percental change of the ratio between slowly progressiv and local motile sperm before …
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Enhanced fertility estimation and novel ion channels in boar sperm
Cryopreserved boar sperm have many potential advantages when used for artificial insemination (AI), including increased time for pathogen testing and ease of semen transport. However, frozen boar sperm are seldom used for AI due to decreased pregnancy rates and litter sizes as a result of …
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Determining the role of nerve growth factor-beta in seminal plasma on bovine reproduction
… systems as well. Most notable is its function in camelids as an ovulation inducing agent with a dose-dependent luteotrophic effect. While also present in the seminal plasma of spontaneously ovulating species, such as the bull, the role of NGF was initially thought to be limited to …