脑缺血对大鼠皮层、海马铁含量及膜铁转运蛋白1的影响

目的 探讨脑缺血对大鼠皮层、海马铁含量及膜铁转运蛋白1（ferroportin1，FP1）的影响。方法 雄性Wistar大鼠60只，随机分为脑缺血1d、3d、7d、28d和假手术对照组，每组各12只。实验组结扎双侧颈总动脉造成大鼠脑缺血，假手术对照组仅分离出双侧颈总动脉但不结扎。应用石墨炉原子吸收分光光度法检测皮层及海马铁含量，应用DAB增强的Perls＇铁染色法观察细胞内铁分布，用免疫组织化学观察FP1在皮层及海马组织中的表达。结果 与假手术对照组相比，脑缺血第7天组皮层、海马铁含量开始增加（P〈0.05），缺血第28天组显著增加（P〈0.01）;缺血第28天组铁染色明显增强，皮层和海马神经元中有大量铁沉积颗粒。正常皮层及海马组织中FP1表达明显，主要定位于锥体神经细胞。而脑缺血第7天FP1表达开始减少，缺血第28天降到最低水平。结论 脑缺血引起了大鼠皮层及海马铁含量升高，神经元中铁沉积;同时引起了FP1表达减少。提示脑缺血后FP1表达减少可能参与了铁的沉积。

Changes of iron concentration and expression of ferroportin 1 in the cortex and hippocampus in rats induced by cerebral ischemia

Objective To explore the effect of ischemia on the iron concentration and the expression of ferroportin 1(FP1)in the cortex and hippocampus in rats.MethodsBilateral common carotid arteries were ligated to induce cerebral ischemia in Wistar rats.The iron concentrations of the cortex and hippocampus in rats were measured by graphite stove atomic absorption spectrometry.Iron was stained by DAB enhanced Perls' reaction.FP1 expression was detected by immunohistochemistry method.ResultsThe iron concentration in the cortex and hippocampus of cerebral ischemic rats began to increase at day 7 and increased significantly at day 28 compared with control rats.There were more iron granules in the neurons of the cortex and hippocampus in ischemic rats compared with control rats.FP1 expression began to decrease in cerebral ischemic rats at day 7,and decreased to the least level at day 28 compared with control rats.ConclusionA series of pathophyologic changes(an increase of iron concentration in the cortex and hippocampus of rats,iron accumulation in neurons and a decrease of FP1 expression)could be induced by cerebral ischemia,which indicates that the decrease of FP1 expression may involve in iron deposition in neurons.