Olivé M, Blanco R, Rivera R, Cinos C, Ferrer I
Unidad de Neuropatología, Hospital Príncipes de España, Universidad de Barcelona, Spain.
J Anat. 1995 Aug;187 ( Pt 1)(Pt 1):127-32.
Newborn Sprague-Dawley rats were exposed to a single dose of 2 Gy gamma rays and killed from 6 h to 5 d later. Increased numbers of dying cells, characterised by their extreme chromatin condensation and often nuclear fragmentation were seen in skeletal muscle 6 h after irradiation. Dying cells decreased to nearly normal values 48 h later. In situ labelling of nuclear DNA fragmentation identified individual cells bearing fragmented DNA. The effects of gamma rays were suppressed following cycloheximide i.p. at a dose of 1 microgram/g body weight given at the time of irradiation. Taken together, the present morphological and pharmacological results suggest that gamma ray induced cell death in skeletal muscle is apoptotic, and that the process is associated with protein synthesis. Finally, proliferating cell nuclear antigen-immunoreactive cells, which were abundant in control rats, decreased in number 48 h after irradiation. However, a marked increase significantly above normal age values was observed at the 5th day, thus suggesting that regeneration occurs following irradiation-induced cell death in developing muscle.
将新生的斯普拉格-道利大鼠暴露于单次2 Gy的γ射线剂量下，并在6小时至5天后处死。照射后6小时，在骨骼肌中可见死亡细胞数量增加，其特征为染色质极度浓缩且常伴有核碎裂。48小时后，死亡细胞数量降至接近正常水平。对核DNA片段化进行原位标记可识别出带有片段化DNA的单个细胞。在照射时腹腔注射剂量为1微克/克体重的环己酰亚胺后，γ射线的作用受到抑制。综合来看，目前的形态学和药理学结果表明，γ射线诱导的骨骼肌细胞死亡是凋亡性的，且该过程与蛋白质合成有关。最后，在对照大鼠中丰富的增殖细胞核抗原免疫反应性细胞在照射后48小时数量减少。然而，在第5天观察到显著高于正常年龄值的明显增加，因此表明发育中的肌肉在照射诱导的细胞死亡后会发生再生。
