Howell R W, Narra V R, Sastry K S, Rao D V
Department of Radiology, University of Medicine and Dentistry of New Jersey, New Jersey Medical School, Newark 07103.
Radiat Res. 1993 Apr;134(1):71-8.
Radionuclides that emit Auger electrons are widely used in nuclear medicine (e.g., 99mTc, 123I, 201Tl) and biomedical research (e.g., 51Cr, 125I), and they are present in the environment (e.g., 40K, 55Fe). Depending on the subcellular distribution of the radionuclide, the biological effects caused by tissue-incorporated Auger emitters can be as severe as those from high-LET alpha particles. However, the recently adopted recommendations of the International Commission on Radiological Protection (ICRP) provide no guidance with regard to calculating the equivalent dose for these radionuclides. The present work, using spermatogenesis in mouse testis as the experimental model, shows that the lethality of the prolific Auger emitter 125I is linearly dependent on the fraction of the radioactivity in the organ that is bound to DNA. This suggests that the equivalent dose for Auger emitters may have a similar linear dependence. Accordingly, a formalism for calculating the equivalent dose for Auger emitters is advanced within the ICRP framework.
发射俄歇电子的放射性核素广泛应用于核医学（如99mTc、123I、201Tl）和生物医学研究（如51Cr、125I），并且它们存在于环境中（如40K、55Fe）。根据放射性核素的亚细胞分布，组织中掺入的俄歇电子发射体所引起的生物学效应可能与高传能线密度的α粒子所造成的效应一样严重。然而，国际放射防护委员会（ICRP）最近采纳的建议并未提供关于计算这些放射性核素当量剂量的指导。本研究以小鼠睾丸中的精子发生作为实验模型，结果表明，多产俄歇电子发射体125I的致死率与器官中与DNA结合的放射性活度分数呈线性相关。这表明俄歇电子发射体的当量剂量可能具有类似的线性相关性。因此，在ICRP框架内提出了一种计算俄歇电子发射体当量剂量的形式体系。
