Evidence that peptides derived from the disintegrin domain of primate fertilin and containing the ECD motif block the binding of human spermatozoa to the zona-free hamster oocyte

Zona-free mammalian oocytes have been observed to fuse, under in vitro conditions, With non-homologous spermatozoa. Taking advantage of this heterologous gamete fusion, we designed a bioassay to test -by means of zona-free hamster oocytes- the fertile ability of human spermatozoa, from semen samples of patients attending an Infertility Clinic. To further validate our bioassay, which Was reported elsewhere, we studied the behavior of gamete membranes during fusion at the ultrastructural level.Zona-free hamster oocytes were mixed in vitro with human spermatozoa. At different times after the start of incubation, oocytes were fixed in 1% glutaraldehyde in 0. 25M cacodylate buffer pH 7. A and post-fixed in 196 osmium tetroxide. After dehydration in acetone, they were embedded in a low viscosity epoxy resin. Ultrathin sections were stained with uranyl acetate and lead citrate and examined with a Phillips 300 electron microscope.

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Interaction of human spermatozoa with the human zona pellucida and zona-free hamster oocyte following capacitation by exposure to human cervical mucus

Gamete Research ◽

10.1002/mrd.1120120106 ◽

1985 ◽

Vol 12 (1) ◽

pp. 47-54 ◽

Cited By ~ 16

Author(s):

John E. Gould ◽

James W. Overstreet ◽

Frederick W. Hanson

Keyword(s):

Zona Pellucida ◽

Cervical Mucus ◽

Human Spermatozoa ◽

Hamster Oocyte

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The Fine Structure of Glycocalyx in Human Spermatozoa. A High Resolution Cytochemical Study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100073647 ◽

1973 ◽

Vol 31 ◽

pp. 640-641

Author(s):

P. Hernández-Jáuregui ◽

A. Sosa ◽

A. González Angulo

Keyword(s):

Negative Charge ◽

Iron Hydroxide ◽

Human Spermatozoa ◽

Surface Coat ◽

Cell Surfaces ◽

Colloidal Iron ◽

Cytochemical Study ◽

Specific Permeability ◽

Extracellular Glycoprotein ◽

Mammalian Spermatozoa

Glycocalyx is the name given by Bennett to the extracellular glycoprotein coat present in some cell surfaces. It appears to play an important role in cell properties such as antigenicity, cell adhesivity, specific permeability, and ATP ase activity. In the sperm this coat can be directly related to such important phenomena as capacitation and fertilization. The presence of glycocalyx in invertebrate spermatozoa has already been demonstrated. Recently Yanagimachi et al. has determined the negative charges on sperm surfaces of mammalian spermatozoa including man, using colloidal iron hydroxide. No mention was made however of the outer surface coat as composed of substances other than those confering a negative charge. The purpose of this work was therefore to determine the presence of a glycocalyx in human spermatozoa using alcian blue and lanthanum staining.

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A High Resolution Cytochemical Study of Nuclear ATPase in Human Spermatozoa

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100116590 ◽

1975 ◽

Vol 33 ◽

pp. 594-595

Author(s):

A. Sosa ◽

L. Calzada

Keyword(s):

High Resolution ◽

Atpase Activity ◽

Nuclear Membrane ◽

Human Sperm ◽

Sperm Nucleus ◽

Human Spermatozoa ◽

Cytochemical Study ◽

Membrane Bound ◽

Sperm Nuclei ◽

Interchromatin Space

The dependence of nuclear metabolism on the function of the nuclear membrane is not well understood. Whether or not the function of the nuclear membrane is partial or totally responsible of the repressed template activity of human sperm nucleus has not at present been elucidated. One of the membrane-bound enzymatic activities which is concerned with the mechanisms whereby substances are thought to cross cell membranes is adenosintriphosphatase (ATPase). This prompted its characterization and distribution by high resolution photogrammetry on isolated human sperm nuclei. Isolated human spermatozoa nuclei were obtained as previously described. ATPase activity was demonstrated by the method of Wachstein and Meisel modified by Marchesi and Palade. ATPase activity was identified as dense and irregularly distributed granules confined to the internal leaflet of the nuclear membrane. Within the nucleus the appearance of the reaction product occurs as homogenous and dense precipitates in the interchromatin space.

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