Sperm function

New guidelines for fertility assessment (traditional Segment I) studies that have shortened the premating dosing schedule (for example, in male rats from 10 weeks to 4 weeks). There has been an increased interest in assessment of spermatogenesis and sperm function. 

Bush B, Bennett AH, Snow JT. 1986. Polychlorobiphenyl congeners, p,p -DDE, and sperm function in humans. Arch Environ Contam Toxicol 15(4) 333-341. 

Neurotoxicity peripheral/spinal cord nerve damage Mating-, reduced hindlimb strength in males leading to reduced copulation activity Fertility, insufficient number of copulations to assure fertilization of female high levels of ROS in ejaculated sperm, functional damage of spermatozoa... 

Sperm evaluations routinely include data on sperm number, morphology and motility (Berman etal., 1996). Testicular spermatid count or cauda epididymal weight are other useful measures of sperm production, but no surrogate measures are adequate to evaluate sperm morphology or motility. A number of other indices of sperm function have been employed (e.g., sperm-zona interactions, acrosome reaction, sperm swelling studies), but these have been of limited utility and infrequently used and have not been incorporated into any testing guidelines. 

Lee, C.H., R. Bagdon, and Y.W. Chien. 1996. Comparative in vitro spermicidal activity and synergistic effect of chelating agents with nonoxynol-9 on human sperm functionality. J Pharm Sci 85 91. 

The more subtle roles of different PMCAs in cardiac and sperm function, synaptic signaling in retina and hippocampus, etc. suggest that these are not housekeeping genes, rather they provide an important function in many cell types and tissues. It seems likely that changes in each of the PMCA isoforms may contribute quantitatively to a number of complex diseases in ways yet to be discovered. 

Evidence to suggest that infertile men have high levels of ROS FIG. 20 Effect of oxidative stress and lycopene on sperm functionality. 

Once a strain is frozen as sperm we strongly recommend that 1-2 straws be used to assess the quality of the sperm post-thaw. Although various devices exist to measure sperm motility etc., the only relevant test for sperm function is an actual IVF. Additionally, fertilization rates vary widely among commonly available inbred strains also the introduction of mutations and genetic modifications into a strain can have indirect and unanticipated effects on the quantity and quality of oocytes and sperm produced, as well their performance during IVF (12, 17). 

Platyhelminths - Eucestoda. In Reproductive biology of invertebrates, vol. II Spermiogenesis and sperm function, ed. K. G. Adiyodi R. G. Adiyodi, pp. 131-49. John Wiley Sons London. 

Hellsten E, Evans JP, Bernard DJ, Janne PA, Nussbaum RL (2001) Disrupted sperm function and fertihn beta processing in mice deficient in the inositol polyphosphate 5-phosphatase Inpp5b. Dev Biol 240 641-653... 

Kricka LJ, Nozaki O, Heyner S, Garside WT, Wilding P. Applications of a microfabricated device for evaluating sperm function. Clin Chem 1993 39 1944-7. 

It has been reported that -50% of infertility problems are male in origin. However, male infertility often goes undetected, because low sperm count or abnormal sperm motility, combmed with normal female reproductive function, merely results in delayed conception. Most infertile men (80%) will not have a definable cause and are said to have so-called idiopathic impaired sperm function. In about 20% of cases, a cause can be determined. A study at Monash University Infertility Clinic in Australia indicated that primary testicular failure accounted for 11% of male patients seen 8.5% had genital tract obstruction, 0.5% had hypothalamic-pituitary disease, and less than 1% had coital disorders or abnormal sperm. A fist of the most common male infertility factors is given in Box 53-4. 

Sperm Function. Functional tests have yet been established that can unequivocally predict the fertilizing capacity of spermatozoa. However, detailed methods describing the analysis of sperm function exist in the current literature. These methods attempt to measure the functions of sperm necessary for fertilization. For a sperm to be successful, it must be able to (1) reach the ova through directed motility, (2) undergo capacitation, (3) fuse with the oocyte membrane, and (4) be incorporated into the oocyte cytoplasm. The postcoital test (as described in the later section on evaluation of female infertility) is the most widely used measure of sperm adequacy. The WHO has accepted and offered guidelines for the postcoital test and the sperm-mucus penetration The sperm-mucus penetration... 

Sager D, Girard D, Nelson D. 1991. Early postnatal exposure to PCBs Sperm function in rats. 

Aitken, R.J., Paterson, M., Fisher, H and Buckingham, D.W. (1995). Van Duin M. Redox regulation of tyrosine phosphorylation in human spermatozoa and its role in the control of human sperm function. J. Cell Sci. /0S 2017-2025... 

Smith, T. (1998). The modulation of sperm function by the oviductal epithelium. Biol. Reprod. 58 1102-1104. 

Aitken, R. J.. and Clarkson. J. S. (1987). Cellular ba.sls of defective sperm function and its association with the genesis of reactive oxygen specie.s by human spermatozoa. J Reprod. Feriil. 81,459-469. 

Schuel, H., Burkman, L.J., Lippes, J., Crickard, K., Mahony, M.C., Giuffrida, A., Picone, R.R, and Makri-yannis, A. (2002) Evidence that anandamide-signaling regulates human sperm functions required for fertilization. Mol Reprod Dev 63 376-387. 

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