title: Measurement of DNA breakage in spermiogenic germ-cell stages of mice exposed to ethylene oxide, using an alkaline elution procedure.
abstract: DNA breakage in spermiogenic stages of the mouse was studied after exposure to ethylene oxide (EtO), using an alkaline elution technique. At daily intervals over a 23-day period following i.p. injection of 100 mg EtO/kg, mature spermatozoa were recovered from treated ([3H]dThd-labeled) and control ([14C]dThd-labeled) animals, lysed together on polycarbonate filters, and the DNA was eluted with a high pH (12.2) buffer. Elution of germ-cell DNA from EtO-exposed animals increased (more DNA strand breaks) in stages sensitive to the genetic effects of EtO (late spermatids to early spermatozoa). The stage-related pattern of EtO-induced DNA breakage paralleled the pattern of sperm alkylation and protamine alkylation found to be produced by EtO in an earlier study (Sega and Owens, 1987). At 9 days posttreatment (sperm sampled were in late-spermatid stages at the time of EtO exposure) the amount of sperm DNA eluted did not change significantly over a pH range of 11.6-12.8, indicating that, at the time of assay, DNA breaks were already present in the sperm.
authors.affiliation: Biology Division, Oak Ridge National Laboratory, TN 37831.
authors.forename: G A
authors.initials: GA
authors.lastname: Sega
authors.forename: E E
authors.initials: EE
authors.lastname: Generoso
mesh_terms: D000818:Animals; D002250:Carbon Radioisotopes; D004247:DNA / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification; D004249:DNA Damage; D004261:DNA Replication / Q000187:drug effects; D005027:Ethylene Oxide / Q000633:toxicity*; D006863:Hydrogen-Ion Concentration; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D013091:Spermatogenesis / Q000187:drug effects*; D013094:Spermatozoa / Q000187:drug effects*; D014316:Tritium
chemical_list: D002250:Carbon Radioisotopes; D014316:Tritium; D004247:DNA; D005027:Ethylene Oxide