Prieditis H, Adamson I Y R
Department of Pathology, University of Manitoba, Winnipeg, Canada.
Exp Lung Res. 2002 Oct-Nov;28(7):563-76. doi: 10.1080/01902140290096782.
The potential toxicity of an atmospheric dust sample EHC-93 has been attributed to the soluble fraction and, more specifically, to the zinc component. The concentration of Zn is the highest among the metals present in the soluble EHC-93 fraction. We now determine whether other metal components of this dust could cause similar lung injury if present at the same concentration as Zn (4.8 mg/g dust). Solutions of Zn, Cu, V, Ni, Fe, and Pb salts in 0.1 mL water were instilled to mouse lung and animals were killed at intervals up to 2 weeks later; each mouse received tritiated thymidine 1 hour before death. Solutions containing Zn and to a lesser degree Cu induced lung injury; in addition, increased numbers of alveolar macrophages and polymorphonuclear leukocytes were found in the lavage fluid, which also contained increased protein levels up to 1 week later. The magnitude of response was similar to that seen after administering EHC-93 dust at 1 mg in 0.1 mL water, whereas the response to other metal solutions containing Ni, Fe, Pb, and V was minimal. Morphologic evidence of lung injury and inflammation was also seen after EHC dust and the Zn or Cu solutions only. Reparative cell proliferation was measured after thymidine uptake and autoradiographs showed increased labeling of lung cells, particularly at 3 and 7 days. Labeling was confined to bronchiolar and type 2 alveolar epithelial cells, indicating previous epithelial cell necrosis in response to Zn or Cu. The results indicate that atmospheric contaminant metals Zn and Cu are most likely to cause lung injury and inflammation as compared to metals such as Ni, Fe, Pb, and V at the same concentrations. It appears that similar toxicity occurs when both redox (Cu) and nonredox (Zn) reactions are involved.
大气尘埃样本EHC - 93的潜在毒性归因于可溶部分，更具体地说，是锌成分。在可溶的EHC - 93部分中存在的金属中，锌的浓度最高。我们现在要确定，如果该尘埃中的其他金属成分以与锌相同的浓度（4.8毫克/克尘埃）存在，是否会导致类似的肺损伤。将锌、铜、钒、镍、铁和铅盐在0.1毫升水中的溶液滴入小鼠肺部，在长达2周的时间间隔内处死动物；每只小鼠在死亡前1小时接受氚标记胸腺嘧啶核苷。含锌溶液以及程度稍轻的含铜溶液会导致肺损伤；此外，在灌洗液中发现肺泡巨噬细胞和多形核白细胞数量增加，直至1周后蛋白质水平也有所升高。反应程度与在0.1毫升水中给予1毫克EHC - 93尘埃后所见相似，而对含镍、铁、铅和钒的其他金属溶液的反应则极小。仅在EHC尘埃以及锌或铜溶液处理后也可见到肺损伤和炎症的形态学证据。在摄取胸腺嘧啶核苷后测量修复性细胞增殖，放射自显影片显示肺细胞标记增加，特别是在第3天和第7天。标记局限于细支气管和Ⅱ型肺泡上皮细胞，表明先前存在对锌或铜的上皮细胞坏死。结果表明，与相同浓度的镍、铁、铅和钒等金属相比，大气污染物金属锌和铜最有可能导致肺损伤和炎症。当涉及氧化还原（铜）和非氧化还原（锌）反应时，似乎会出现类似的毒性。
