Sperm motility

About: Sperm motility is a research topic. Over the lifetime, 13874 publications have been published within this topic receiving 416587 citations. The topic is also known as: sperm movement & GO:0097722.

Effects of white blood cells on the in vitro penetration of zona-free hamster eggs by human spermatozoa.

Abstract: The presence of white blood cells in semen has been associated with male infertility. Previous studies indicate that pyospermia occurs in conjunction with decreases in sperm motility, number of normal sperm forms, and penetration rates in the zona-free hamster egg sperm penetration assay. We have evaluated the relationship of seminal white blood cells and sperm function, as reflected in the zona-free hamster egg penetration assay, and have investigated the possible mode of action of the white cells. Egg penetration rates decreased when white blood cells from fertile or potentially fertile donors were added to their sperm suspensions prior to preincubation and at insemination in the in vitro assay. Zona-free hamster egg penetration assay results were also inhibited when the supernatant from white blood cells incubated in Biggers, Whitten, and Whittingham (BWW) medium overnight were introduced to sperm-oocyte suspensions at insemination. Conversely, egg penetration rates were enhanced in samples from hypofertile individuals when white blood cell concentrations in the semen or WBC/sperm ratios were reduced, either by physical removal or as a result of antibiotic therapy. The physical presence of leukocytes, and possibly, the extracellular release of lysosomal enzymes may be responsible for the inhibitory effects in vitro. Although the mechanism(s) by which white blood cells interfere with the fertilizing capacity of spermatozoa are not clear, it is quite obvious that their presence in the in vitro environment is undesirable and can mask an individual's actual fertilizing potential.

Micromanipulation of sperm by a laser generated optical trap - eScholarship

Abstract: The force generated by the radiation pressure of a low power laser beam induces an optical trap which may be used to manipulate sperm. We studied the effect of the optical trap on sperm motility. A Nd:YAG laser beam was coupled to a conventional microscope and focused into the viewing plane by the objective lens. Sperm were caught in the trap and manipulated by a joy stick controlled motorized stage. After different exposure periods, the velocity and patterns were analysed by a computerized image processor. There were minor changes in sperm velocity when exposed to the trap for 30 seconds or less. A gradual decrease in the mean linear velocity was observed after 45 seconds of exposure. This optical micromanipulator may also be useful for studying the force generated by a single spermatozoa and evaluating the influence of drugs on motility.

Associations between urinary phthalate concentrations and semen quality parameters in a general population

Abstract: STUDY QUESTION Are urinary phthalate concentrations associated with altered semen quality parameters among males recruited from the general population? SUMMARY ANSWER Urinary levels of metabolites of phthalate diesters are associated with lower total sperm counts, larger sperm head sizes, and higher percentages of morphologically abnormal sperm. WHAT IS KNOWN ALREADY High dose experiments in rats implicate phthalates as anti-androgens. Studies involving infertile men seeking care suggest that phthalates influence measures of semen quality raising concern about the implications for men in the general population. STUDY DESIGN, SIZE, DURATION This prospective cohort study comprised 501 male partners in couples discontinuing contraception to become pregnant, who were recruited from 16 US counties using population-based sampling frameworks from 2005 to 2009. PARTICIPANTS/MATERIALS, SETTING, METHODS Urine and semen samples were obtained at baseline from 473 (94%) men, of whom 378 (80%) men provided a second sample the following month. Urine was analyzed for 14 monoester metabolites of phthalate diesters by high-performance liquid chromatography coupled to tandem mass spectrometry. Semen samples were analyzed for 34 quality parameters categorized as general, motility, morphology, sperm head and sperm chromatin structure. MAIN RESULTS AND THE ROLE OF CHANCE Urinary mono-[2-(carboxymethyl) hexyl] phthalate (MCMHP), mono-(2-ethyl-5-hydroxyhexyl) phthalate (MEHHP), mono-benzyl phthalate (MBzP), and mono-isononyl phthalate (MNP) were significantly associated with lower total sperm counts and concentrations, larger sperm head sizes, higher proportions of megalo head sperm morphology, and/or other morphological changes. Urinary mono-methyl phthalate (MMP) and mono-cyclohexyl phthalate (MCPP) were significantly associated with lower sperm motility, and urine mono-2-ethylhexyl phthalate (MEHP) was significantly associated with higher sperm motility. LIMITATIONS, REASONS FOR CAUTION While adverse associations were observed, the implications of the findings for couple fecundity and fertility remain to be established. Cautious interpretation is needed in light of reliance on a single measurement of phthalate measure and no correction for multiple comparisons.

Characterization of temperature-sensitive, fertilization-defective mutants of the nematode caenorhabditis elegans

Abstract: The isolation and characterization of three Caenorhabditis elegans temperature-sensitive mutants that are defective at fertilization are described. All three are alleles of the gene fer-1. At the restrictive temperature of 25°, mutant hermaphrodites make sperm and oocytes in normal numbers. No oocytes are fertilized, although they pass through the spermatheca and uterus normally. The oocytes can be fertilized by sperm transferred by wild-type males, indicating that the mutant defect is in the sperm. The temperature-sensitive period for the mutants coincides with spermatogenesis. Sperm made by mutants at 25° cannot be distinguished from wild-type sperm by light microscopy. The sperm do contact oocytes in mutant hermaphrodites, but do not fertilize. Mutant sperm appear to be nonmotile. Mutant males are also sterile when grown at 25°. They transfer normal numbers of sperm to hermaphrodites at mating, but these sperm fail to migrate to the spermatheca and are infertile. The phenotype of these mutants is consistent with a primary defect in sperm motility, but the cause of this defect is not known.

Rat sperm are mechanically immobilized in the caudal epididymis by "immobilin," a high molecular weight glycoprotein.

Abstract: In many mammals, sperm are immotile while stored in the caudal epididymis and do not become motile until ejaculation. We report here our investigation of the mechanism that initiates motility in mature rat epididymal sperm. We found that an external "activator" is not required to initiate rat sperm motility since immotile sperm started to swim immediately when exposed to solutions that contributed only osmotic support. Instead, we found that epididymal rat sperm are kept fully immobilized by a high molecular weight glycoprotein, "immobilin," that we have isolated from rat cauda epididymal (CE) fluid. Our results strongly support the hypothesis that immobilin inhibits sperm motility mechanically simply by creating a highly viscoelastic environment: 1) rat CE fluid inhibited the motility of such disparate cells as rat sperm, E. coli. and rabbit sperm (which are fully motile in rabbit CE fluid), 2) the degree to which a variety of enzymatic treatments or slight dilution of the CE fluid initiated sperm motility depended only on the degree to which the treatment reduced the viscoelastic drag of the fluid, and 3) centrifugation of CE fluid simultaneously copurified the component of the fluid that immobilizes the sperm, the component that renders the fluid viscoelastic, and the glycoprotein immobilin.