Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
1989-2-23
pubmed:abstractText
To assess the structural stability of mammalian sperm nuclei and make interspecies comparisons, we microinjected sperm nuclei from six different species into hamster oocytes and monitored the occurrence of sperm nuclear decondensation and male pronucleus formation. The time course of sperm decondensation varied considerably by species: human and mouse sperm nuclei decondensed within 15 to 30 min of injection, and chinchilla and hamster sperm nuclei did so within 45 to 60 min, but bull and rat sperm nuclei remained intact over this same period of time. Male pronuclei formed in oocytes injected with human, mouse, chinchilla, and hamster sperm nuclei, but rarely in oocytes injected with bull or rat sperm nuclei. However, when bull sperm nuclei were pretreated with dithiothreitol (DTT) in vitro to reduce protamine disulfide bonds prior to microinjection, they subsequently decondensed and formed pronuclei in the hamster ooplasm. Condensed rat spermatid nuclei, which lack disulfide bonds, behaved similarly. The same six species of sperm nuclei were induced to undergo decondensation in vitro by treatment with DTT and detergent, and the resulting changes in nuclear size were monitored by phase-contrast microscopy and flow cytometry. As occurred in the oocyte, human sperm nuclei decondensed the fastest in vitro, followed shortly by chinchilla, mouse, and hamster and, after a lag, by rat and bull sperm nuclei. Thus species differences in sperm nuclear stability exist and appear to be related to the extent and/or efficiency of disulfide bonding in the sperm nuclei, a feature that may, in turn, be determined by the type(s) of sperm nuclear protamine(s) present.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Aug
pubmed:issn
0006-3363
pubmed:author
pubmed:issnType
Print
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
157-67
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1988
pubmed:articleTitle
Interspecies differences in the stability of mammalian sperm nuclei assessed in vivo by sperm microinjection and in vitro by flow cytometry.
pubmed:affiliation
Reproductive Toxicology Branch, U.S. Environmental Protection Agency, Research Triangle Park, North Carolina 27711.
pubmed:publicationType
Journal Article, Comparative Study