Ghosh Somnath, Kumar Amit, Pandey Badri Narain, Mishra Kaushala Prasad
Radiation Biology and Health Sciences Division, Bhabha Atomic Research Centre, Mumbai-400 085, India.
J Environ Pathol Toxicol Oncol. 2007;26(4):255-61. doi: 10.1615/jenvironpatholtoxicoloncol.v26.i4.20.
Although the kidneys are the main target organs for uranium (U) toxicity, recent studies have shown that U can cross the blood-brain barrier to accumulate in the brain. Uranyl nitrate (U-238)induced oxidative damage was investigated in brain and bone of Wistar rats after intraperitoneal injection of uranyl nitrate at acute doses either nephrotoxic (576 microg of U/kg body weight) or subnephrotoxic (144 microg U/kg body weight). The health effects of U administration at 576 microg of U/kg body weight were seen in terms of decrease in food intake and no gain in body weight compared to respective controls. These alterations were correlated with increased lipid peroxidation as measured by thiobarbituric acid reactive substances in rat brain and bone. However, at lower dosage of U (144 microg U/kg body weight), no significant lipid peroxidation was observed in brain and bone. Histological examination of U-treated (576 microg of U/kg body weight) rat brain tissues showed marked and diffuse cystic degeneration and a similar pattern in histological alterations was observed in kidneys in treated animals; whereas no significant histological change was observed in rat brains and kidney treated with a lower dose of U (144 microg U/kg body weight). It is concluded that administration of U at an acute nephrotoxic dose caused oxidative stress in brain and bone manifested as lipid peroxidation and histopathological damage.
尽管肾脏是铀(U)毒性的主要靶器官,但最近的研究表明,铀能够穿过血脑屏障并在大脑中蓄积。在Wistar大鼠腹腔注射急性剂量的硝酸铀酰(U-238)后,研究了其对大脑和骨骼的氧化损伤,急性剂量分为肾毒性剂量(576微克铀/千克体重)或亚肾毒性剂量(144微克铀/千克体重)。与各自的对照组相比,以576微克铀/千克体重剂量给予铀时,可见食物摄入量减少且体重未增加等健康影响。这些变化与大鼠大脑和骨骼中通过硫代巴比妥酸反应性物质测定的脂质过氧化增加相关。然而,在较低剂量的铀(144微克铀/千克体重)下,大脑和骨骼中未观察到明显的脂质过氧化。对经铀处理(576微克铀/千克体重)的大鼠脑组织进行组织学检查显示出明显且弥漫性的囊性变性,并且在处理动物的肾脏中观察到了类似的组织学改变模式;而在以较低剂量铀(144微克铀/千克体重)处理的大鼠大脑和肾脏中未观察到明显的组织学变化。得出的结论是,以急性肾毒性剂量给予铀会导致大脑和骨骼中的氧化应激,表现为脂质过氧化和组织病理学损伤。