title: Micronucleus formation in 2-cell embryos after in vitro X-irradiation of mouse spermatozoa.
abstract: Mouse spermatozoa were exposed in vitro to various X-ray doses and added to a medium containing superovulated oocytes. The percentage of fertilized oocytes was determined 24 h after sperm addition and 2-cell embryos were investigated for micronucleus formation. The fertilization rate was drastically decreased after exposure to 470 cGy whereas smaller doses had no effect. The dose-response relationship for micronucleus formation per embryo was linear-quadratic and the number of embryos with micronuclei increased linearly with dose. The distribution of micronuclei among 2-cell embryos showed a significant overdispersion relative to the Poisson distribution after sperm irradiation for doses above 188 cGy.
authors.affiliation: Institut für Medizinische Strahlenbiologie, Universitätsklinikum Essen, F.R.G.
authors.forename: S
authors.initials: S
authors.lastname: Pampfer
authors.forename: C
authors.initials: C
authors.lastname: Streffer
authors.forename: W U
authors.initials: WU
authors.lastname: Müller
mesh_terms: D000818:Animals; D002869:Chromosome Aberrations; D002970:Cleavage Stage, Ovum / Q000648:ultrastructure; D004307:Dose-Response Relationship, Radiation; D005307:Fertilization in Vitro; D066298:In Vitro Techniques; D008297:Male; D051379:Mice; D015162:Micronucleus Tests / Q000379:methods*; D013094:Spermatozoa / Q000528:radiation effects*; D014965:X-Rays