Intracellular distribution and radiotoxicity of chromium-51 in mammalian cells: Auger-electron dosimetry.
The kinetics of uptake and of radiotoxicity of chromium-51, an Auger-electron emitter, have been studied in V79 lung fibroblasts of the Chinese hamster. Intracellular radioactivity was directly proportional to the incubation period and to the extracellular concentration of the Cr-51. About 14% of the cellular activity was associated with the nucleus, whereas approximately 2% was guanidine-precipitable and therefore bound to DNA. The growth rate of V79 cells was slowed following intracellular incorporation of Cr-51. The cell-survival curve, in terms of colony-forming ability, was of the low-LET type, with a D37 of 6.2 pCi/cell. Theoretical dosimetric estimates indicate that, under the given experimental conditions, the mean lethal dose to the cell nucleus was 870 rad. Although this value is somewhat larger than the x-ray D37 dose of 580 rad for this cell line, it is more realistic than the gross underestimate obtained by classical MIRD calculations (2-3 rad/cell).
D000818:Animals; D002460:Cell Line; D002467:Cell Nucleus / Q000528:radiation effects; D002470:Cell Survival / Q000528:radiation effects; D002860:Chromium Radioisotopes / Q000009:adverse effects; D006224:Cricetinae; D003412:Cricetulus; D004583:Electrons; D005347:Fibroblasts / Q000166:cytology / Q000528:radiation effects; D006207:Half-Life; D007700:Kinetics; D011829:Radiation Dosage
D002860:Chromium Radioisotopes