Gobé G C, Axelsen R A, Harmon B V, Allan D J
Department of Pathology, University of Queensland Medical School, Herston, Brisbane, Australia.
Int J Radiat Biol. 1988 Oct;54(4):567-76. doi: 10.1080/09553008814552011.
A light and electron microscopic study was undertaken to determine the type of cell death induced by X-irradiation in the developing kidney. Five-day-old Sprague-Dawley rats were exposed to a whole-body dose of either 2 or 5 Gy, and foetuses in the eighteenth day of development were exposed to a dose of 4 Gy. The kidneys were examined at 4, 8 and 24 h, and at 1 and 2 weeks post-irradiation. The dying cells from both control and treated kidneys showed the morphological features of apoptosis, a distinct form of cell death that has been identified in mammalian tissues under physiological as well as pathological conditions. Necrosis was not detected. Apoptosis was infrequent in control kidneys and insignificant in extent when compared with the proliferative activity of the cells of the superficial nephrons. There was a pronounced increase in apoptosis during the first day after irradiation. The findings are in agreement with recent ultrastructural studies which report the presence of apoptosis following irradiation of rapidly proliferating adult cell populations, and irradiation of other immature mammalian tissues. There is evidence that apoptosis involves active cellular self-destruction, and it has been suggested that activation of apoptosis might bring about selective elimination of cells with critical DNA damage in irradiated tissues, thus minimizing propagation of genetic abnormalities.
进行了一项光镜和电镜研究，以确定发育中的肾脏中X射线照射诱导的细胞死亡类型。对5日龄的Sprague-Dawley大鼠进行全身2或5 Gy剂量的照射，对发育第18天的胎儿进行4 Gy剂量的照射。在照射后4、8和24小时以及1和2周时检查肾脏。来自对照和处理过的肾脏的死亡细胞表现出凋亡的形态特征，凋亡是一种在生理和病理条件下在哺乳动物组织中已被识别的独特细胞死亡形式。未检测到坏死。与浅表肾单位细胞的增殖活性相比，对照肾脏中的凋亡很少见且程度不明显。照射后第一天凋亡明显增加。这些发现与最近的超微结构研究一致，这些研究报告了快速增殖的成年细胞群体照射以及其他未成熟哺乳动物组织照射后存在凋亡。有证据表明凋亡涉及活跃的细胞自我破坏，并且有人提出凋亡的激活可能导致选择性消除受照射组织中具有严重DNA损伤的细胞，从而使遗传异常的传播最小化。
