Fleming J, Joshi J G
Department of Biochemistry, University of Tennessee, Knoxville 37996.
Proc Natl Acad Sci U S A. 1987 Nov;84(22):7866-70. doi: 10.1073/pnas.84.22.7866.
Ferritin was isolated from the livers and brains of two groups of rats, one of which was fed aluminum chloride (100 microM) for 1 year in the drinking water. Brain tissue contained about one-third of the amount of ferritin found in the liver. While brain ferritin from normal rats contained 42.1 +/- 14.3 mol of aluminum, that from the aluminum-fed group contained 115.4 +/- 48.3 mol of aluminum per mol of ferritin. Liver ferritin from both groups contained similar amounts of both aluminum and iron, and the amounts were less than that found associated with brain ferritin. Ferritin isolated from the brains of patients who died of Alzheimer disease contained more aluminum and more iron than that from age-matched controls. Human brain ferritin is composed of two types of subunits--about 70% heavy chain (Mr, 22,000) and 30% light chain (Mr, 19,500). The isoelectric focusing pattern of human brain ferritin was considerably different from that of human liver. Only 5 of the 20 brain ferritin bands migrated similarly to the acidic isoferritins from the liver, and the major component of brain ferritin, representing 30% of the total ferritin, had a pI of 8.0.
从两组大鼠的肝脏和大脑中分离出铁蛋白，其中一组大鼠在饮用水中喂食氯化铝（100微摩尔），持续1年。脑组织中的铁蛋白含量约为肝脏中的三分之一。正常大鼠脑铁蛋白每摩尔含有42.1±14.3摩尔铝，而喂食铝的组中每摩尔铁蛋白含有115.4±48.3摩尔铝。两组大鼠肝脏铁蛋白中的铝和铁含量相似，且含量低于与脑铁蛋白相关的含量。从死于阿尔茨海默病患者大脑中分离出的铁蛋白比年龄匹配对照组的含有更多的铝和铁。人脑铁蛋白由两种亚基组成——约70%为重链（分子量22,000），30%为轻链（分子量19,500）。人脑铁蛋白的等电聚焦图谱与人类肝脏的有很大不同。20条脑铁蛋白条带中只有5条与肝脏中的酸性异铁蛋白迁移情况相似，脑铁蛋白的主要成分占总铁蛋白的30%，其pI为8.0。
