Das B, Khatoon N, Srivastava R C, Viswanathan P N, Rahman Q
Environ Res. 1983 Dec;32(2):372-81. doi: 10.1016/0013-9351(83)90119-6.
Biochemical alterations in guinea pig lungs caused by hematite dust were followed at 150 days after intratracheal administration of the dust. In vivo dust exposure caused a significant increase in mitochondrial protein content and cytochrome c oxidase activity whereas diaphorase activity remained unaltered. Mitochondria from the exposed animals were apparently in a swollen state and their contraction profile upon the addition of ATP reflected permeability changes. However, in vitro dust caused no significant alterations. Significant increases in glycogen content along with an insignificant decrease in glycogen phosphorylase activity were also observed in hematite-treated guinea pig lungs. Decrease in drug-metabolizing enzymes such as aniline hydroxylase and tyrosine aminotransferase activities were also evident in the postmitochondrial fraction of the siderotic lungs. [3H]Leucine-incorporation studies showed increased protein synthesis in the postmitochondrial fraction. Increase in protein synthesis in mitochondria was only marginal whereas in whole homogenate it decreased considerably. Experiments employing dust tagged with radioactive iron indicated the rapid mobilization of iron from lung and its distribution to various organs. The presence of iron-binding protein was confirmed by employing Sephadex gel-filtration techniques.
在气管内注入赤铁矿粉尘150天后，对豚鼠肺部因赤铁矿粉尘引起的生化变化进行了跟踪研究。体内粉尘暴露导致线粒体蛋白含量和细胞色素c氧化酶活性显著增加，而黄递酶活性保持不变。暴露动物的线粒体明显处于肿胀状态，添加ATP后其收缩情况反映了通透性变化。然而，体外粉尘未引起显著变化。在经赤铁矿处理的豚鼠肺部还观察到糖原含量显著增加，同时糖原磷酸化酶活性略有下降。在铁沉着肺的线粒体后组分中，药物代谢酶如苯胺羟化酶和酪氨酸转氨酶活性的降低也很明显。[3H]亮氨酸掺入研究表明线粒体后组分中的蛋白质合成增加。线粒体中蛋白质合成的增加仅为微量，而在全匀浆中则显著下降。使用放射性铁标记粉尘的实验表明，铁从肺部快速转移并分布到各个器官。通过使用葡聚糖凝胶过滤技术证实了铁结合蛋白的存在。
