title: Size of lethality target in mouse immature oocytes determined with accelerated heavy ions.
abstract: Mouse immature oocytes were irradiated in vivo with highly charged, heavy ions from the Bevalac accelerator at the Lawrence Berkeley Laboratory. The particles used were 670-MeV/nucleon Si14+, 570-MeV/nucleon Ar18+, and 450-MeV/nucleon Fe26+. The cross-sectional area of the lethality target in these extremely radiosensitive cells was determined from fluence-response curves and information on energy deposition by delta rays. Results indicate a target cross-section larger than that of the nucleus, one which closely approximates the cross-sectional area of the entire oocyte. For 450-MeV/nucleon Fe26+ particles, the predicted target cross-sectional area is 120 +/- 16 microns2, comparing well with the microscopically determined cross-sectional area of 111 +/- 12 microns2 for these cells. The present results are in agreement with our previous target studies which implicate the oocyte plasma membrane.
authors.affiliation: Environmental Science Division, Lawrence Livermore National Laboratory, University of California 94550.
authors.forename: T
authors.initials: T
authors.lastname: Straume
authors.forename: R L
authors.initials: RL
authors.lastname: Dobson
authors.forename: T C
authors.initials: TC
authors.lastname: Kwan
mesh_terms: D000818:Animals; D001128:Argon; D002452:Cell Count / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D004601:Elementary Particles; D004735:Energy Transfer; D005260:Female; D007477:Ions; D007501:Iron; D051379:Mice; D009865:Oocytes / Q000528:radiation effects*; D012825:Silicon; D014916:Whole-Body Irradiation
chemical_list: D007477:Ions; D001128:Argon; D007501:Iron; D012825:Silicon