Shukla A, Agarwal K N, Shukla G S
Department of Pediatrics, Banaras Hindu University, Varanasi, India.
Biol Trace Elem Res. 1989 Nov;22(2):141-52. doi: 10.1007/BF02916645.
Seven different metals (iron, copper, zinc, calcium, manganese, lead, and cadmium) were studied in eight different brain regions (cerebral cortex, cerebellum, corpus striatum, hypothalamus, hippocampus, midbrain, medulla oblongata, and pons) of weaned rats (21-d-old) maintained on an iron-deficient (18-20 mg iron/kg) diet for 8 wk. Iron was found to decrease in all the brain regions, except medulla oblongata and pons, in comparison to their respective levels in control rats, receiving an iron-sufficient (390 mg iron/kg) diet. Brain regions showed different susceptibility toward iron deficiency-induced alterations in the levels of various metals, such as zinc, was found to increase in hippocampus (19%, p less than 0.05) and midbrain (16%, p less than 0.05), copper in cerebral cortex (18%, p less than 0.05) and corpus striatum (16% p less than 0.05), calcium in corpus striatum (22%, p less than 0.01) and hypothalamus (17%, p less than 0.02), and manganese in hypothalamus (18%, p less than 0.05) only. Toxic metals lead and cadmium also increased in cerebellum (19%, p less than 0.05) and hippocampus (17%, p less than 0.05) regions, respectively. Apart from these changes, liver (64%, p less than 0.001) and brain (19%, p less than 0.01) nonheme iron contents were found to decrease significantly, but body, liver, and brain weights, packed cell volume, and hemoglobin content remained unaltered in these experimental rats. Rehabilitation of iron-deficient rats with an iron-sufficient diet for 2 wk recovered the values of zinc in both the hippocampus and mid-brain regions and calcium in the hypothalamus region only. Liver nonheme iron improved significantly; however, no remarkable effect was noticed in brain nonheme iron following rehabilitation. It may be concluded that latent iron deficiency produced alterations in various metal levels in different brain regions, and corpus striatum was found to be the most vulnerable region for such changes. It is also evident that brain regions were resistant for any recovery in their altered metallic levels in response to rehabilitation for 2 wk.
对断乳大鼠（21日龄）进行研究，这些大鼠以缺铁（18 - 20毫克铁/千克）饮食维持8周，之后检测其八个不同脑区（大脑皮层、小脑、纹状体、下丘脑、海马体、中脑、延髓和脑桥）中的七种不同金属（铁、铜、锌、钙、锰、铅和镉）。与摄入铁充足（390毫克铁/千克）饮食的对照大鼠的相应水平相比，发现除延髓和脑桥外，所有脑区的铁含量均下降。脑区对缺铁诱导的各种金属水平变化表现出不同的敏感性，例如，海马体（升高19%，p < 0.05）和中脑（升高16%，p < 0.05）中的锌含量增加，大脑皮层（升高18%，p < 0.05）和纹状体（升高16%，p < 0.05）中的铜含量增加，纹状体（升高22%，p < 0.01）和下丘脑（升高17%，p < 0.02）中的钙含量增加，仅下丘脑（升高18%，p < 0.05）中的锰含量增加。有毒金属铅和镉在小脑（升高19%，p < 0.05）和海马体（升高17%，p < 0.05）区域也分别增加。除了这些变化外，还发现肝脏（降低64%，p < 0.001）和大脑（降低19%，p < 0.01）的非血红素铁含量显著下降，但这些实验大鼠的体重、肝脏和大脑重量、血细胞比容和血红蛋白含量保持不变。用铁充足的饮食对缺铁大鼠进行2周的恢复治疗后，仅海马体和中脑区域的锌含量以及下丘脑区域的钙含量恢复到正常水平。肝脏非血红素铁显著改善；然而，恢复治疗后大脑非血红素铁没有明显变化。可以得出结论，潜在缺铁会导致不同脑区各种金属水平发生变化，纹状体是这些变化最敏感的区域。同样明显的是，脑区对恢复治疗2周后其改变的金属水平的任何恢复都具有抗性。
