Rat sperm structure

Although the research described herein has been funded in part by the U. Environmental Protection Agency, it does not necessarily reflect the views of the agency and no official endorsement should be inferred. Wilma De G. Kempinas, Juan D.

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Mouse sperm acquire a new structure on the apical hook during epididymal maturation

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Mouse sperm acquire a new structure on the apical hook during epididymal maturation

Spermatozoa emerging from the testis undergo a maturation process in the epididymis during which they change morphologically, biochemically and physiologically to gain motility and the ability to fertilize ova. We examined mouse epididymal sperm with immunostaining and transmission electron microscopy EM and identified a previously unknown structure on the apical hook. Surveying sperm isolated from various regions of the epididymis indicated that mouse sperm acquire the hook rim HR structure during its passage through the proximal two-thirds of the caput epididymidis. The structure withstands vigorous sonication and harsh chemical treatments and remains intact after the acrosome reaction. Its location and sturdiness suggest a function in protecting the apical hook from mechanical wear during fertilization. Our EM images of epididymal sperm also revealed additional novel structures as well as lateral asymmetry of the sperm head, indicating that mouse sperm head has a structure more complex than previously recognized.
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Rat sperm morphology

Metrics details. Humans are ubiquitously exposed to multiple environmental contaminants. Consequences of combined action on the reproductive system remain unknown.
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It was further indicated that tailor made modules exist for sperm motility, vitality, fragmentation and that in principle it was possible to threshold rat sperm for measurement of sperm morphometry after staining with SpermBlue. However, the cut-off values for these morphometric values to determine the percentage normal sperm morphology has been lacking. Firstly, a detailed method how to quantitatively determine the percentage normal sperm morphology in almost any animal species, and secondly, the specific cut-off values for laboratory Wistar and Sprague-Dawley rats have been performed.
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