Nagamine T, Nakazato K, Suzuki K, Kusakabe T, Sakai T, Oikawa M, Satoh T, Kamiya T, Arakawa K
Faculty of Medicine, Course of Health Science, Gunma University Graduate School of Medical Science, 3-39-15 Showamachi, Maebashi, Gunma, 371-8514, Japan.
Biol Trace Elem Res. 2007 Summer;117(1-3):115-26. doi: 10.1007/BF02698088.
This study undertook the analysis of tissue cadmium (Cd) distribution using in-air micro-particle-induced X-ray emission (PIXE) and the examination of the involvement of metal ions in parenteral Cd toxicity. A mouse was injected intraperitoneally with 3 mg/kg body weight of CdCl2 thrice weekly. After 27 wk, the liver and kidney were excised and fixed in 10% formalin solution for 4 h and then embedded in paraffin. Thin paraffin sections were used to analyze trace elements with in-air micro-PIXE and to examine metallothionein protein and histological changes. Cd distribution was determined by micro-PIXE in the liver and renal cortex of the Cd-exposed mouse, and the net Cd count was higher in the liver than in the renal cortex. The net iron (Fe) count was higher in the liver of the Cd-exposed mouse compared to the control, and an opposite tendency was observed in the renal cortex. Wide cellular Cd distribution was demonstrated in the liver and renal cortex of the chronic Cd-exposed mouse compared to the control. Metallothionein staining was increased by chronic exposure to Cd both in the liver and kidney, and nephrotoxicity was more apparent than hepatotoxicity. The modification of tissue Fe and calcium distribution by an intraperitoneal injection of Cd might be involved in Cd-induced toxicity.
本研究采用空气中微粒子诱导X射线发射（PIXE）分析组织镉（Cd）分布，并研究金属离子在胃肠外Cd毒性中的作用。每周三次给小鼠腹腔注射3mg/kg体重的CdCl2。27周后，切除肝脏和肾脏，在10%福尔马林溶液中固定4小时，然后石蜡包埋。用薄石蜡切片通过空气中微PIXE分析微量元素，并检测金属硫蛋白和组织学变化。通过微PIXE测定Cd暴露小鼠肝脏和肾皮质中的Cd分布，肝脏中的净Cd计数高于肾皮质。与对照组相比，Cd暴露小鼠肝脏中的净铁（Fe）计数更高，而在肾皮质中观察到相反的趋势。与对照组相比，慢性Cd暴露小鼠的肝脏和肾皮质中显示出广泛的细胞Cd分布。长期暴露于Cd会增加肝脏和肾脏中金属硫蛋白的染色，并且肾毒性比肝毒性更明显。腹腔注射Cd对组织Fe和钙分布的改变可能与Cd诱导的毒性有关。
