Eisenbrandt D L, Phemister R D
Lab Invest. 1977 Nov;37(5):437-46.
The effects of radiation on the developing canine kidney were investigated. Beagles were exposed to 330 R 60Co gamma-radiation on the 2nd postnatal day of life. The kidneys were examined at 2 days (6 hours after irradiation), 4, 8, 14, 22, 70, and 200 days of age with qualitative and quantitative light microscopy and scanning electron microscopy. The primary result of the radiation injury was a failure to form the normal number of nephrons. The kidneys of irradiated dogs had 42 per cent fewer nephrons (260,000) than the control dogs (445,000). In addition, extensive damage to forming nephrons produced dysplastic renal corpuscles and other corpuscles which were arrested in their development. Three mechanisms of radiation injury were identified. First, there was extensive mitosis-linked cell death in the nephrogenic zone. Second, mitotic delay resulted in only one-fifth of the normal mitotic activity in the nephrogenic zone through 2 days postirradiation. Third, there was an immediate and permanent cessation of nephron formation. The extensive injury in the outer renal cortex was compounded by the development of intercapillary glomerulosclerosis in some middle and inner cortical corpuscles by 200 days of age.
研究了辐射对发育中的犬肾的影响。比格犬在出生后第2天接受330伦琴的60钴γ射线辐射。在2天（照射后6小时）、4、8、14、22、70和200日龄时，用定性和定量光学显微镜及扫描电子显微镜检查肾脏。辐射损伤的主要结果是未能形成正常数量的肾单位。受辐射犬的肾脏肾单位数量（260,000个）比对照犬（445,000个）少42%。此外，正在形成的肾单位受到广泛损伤，导致发育异常的肾小体和其他在发育过程中停滞的小体。确定了三种辐射损伤机制。第一，在肾发生区有广泛的与有丝分裂相关的细胞死亡。第二，有丝分裂延迟导致照射后2天内肾发生区的有丝分裂活性仅为正常的五分之一。第三，肾单位形成立即且永久停止。到200日龄时，一些中皮质和内皮质小体出现毛细血管间肾小球硬化，加重了肾外皮质的广泛损伤。
