裂片~(147)Pm在肝及胚肝中的滞留诱发肝及胚肝细胞突变效应比较研究

考虑到肝脏是~(147)Pm污染早期滞留和作用的主要靶器官,本研究对~(147)Pm在肝及胚肝中的滞留和诱发肝及胚肝细胞染色体畸变效应进行了对比观察。发现当~(147)Pm摄入机体后,在再生肝中的滞留量要比在同期胚肝中高出700倍之多,估算在再生肝中的累积吸收剂量为2.87Gy,而在胚肝中只有0.004Gy。这与胎盘的屏障作用密切相关,起到了对胚胎细胞的保护作用。在此条件下~(147)Pm诱发再生肝细胞的染色体畸变率为50.2％,而对胚肝细胞则为28.3％,二者之差不到一倍。由此可见胚肝细胞对~(147)Pm的辐射敏感性要比再生肝细胞高得多。至于从~(147)Pm对再生肝及胚肝细胞所诱发的染色体畸变类型来看,则都以染色单体型畸变为主。

COMPARATIVE RETENTION OF FISSION FRAGMENT ~(147)Pm IN REGENERATED AND FETAL LIVER ON INDUCTION OF CHROMOSOME ABERRATIONS IN THESE CELLS

The purpose of the present study is to ascertain comparative reten-tion of fission fragment ~(147)Pm in regenerated and fetal liver on induction. of chro-mosome aberrations in these cells. The results indicated that retention of ~(147)Pm inregenerated liver was about 700 times than in fetal liver. The cumulative absorptiondose in regenerated liver was about 2.87Gy, while in fetal liver-only 0.004 Gy.Under the same conditions, the incidence rate of chromosome aberrations in regenerated.liver cells induced by ~(147)Pm was 50.2%, and in fetal liver cells-about 28.3%. Itshould be concluded that the radiosensitivity to ~(147)Pm was not uniform among theregenerated and fetal liver cells. Our study suggested that fetal liver cells show to bemore radiosensitive to ~(147)Pm than regenerated liver cells. Among the type of aberra-tions in both cells induced by ~(147)Pm, chromatid breakages were predominant, accom-panied with a few chromosome breakages.