铁缺乏对学习记忆能力的影响及其机理的实验研究

STUDY ON THE EFFECT OF IRON DEFICIENCY ON LEARNING AND MEMORY AND ITS MECHANISM IN RAT

用低铁饮食建立铁缺乏大鼠模型，观察铁缺乏对大鼠学习记忆能力的影响及脑组织生化、超微结构的改变。结果：１．铁缺乏非贫血大鼠学习记忆能力有降低趋势，而缺铁性贫血大鼠学习记忆能力明显降低；２．铁缺乏非贫血大鼠脑组织铁含量及单胺氧化酶活性显著低于对照组，大脑皮层去甲肾上腺素及５－羟色胺含量高于对照组，海马５－羟吲哚乙酸含量低于对照组，缺铁性贫血大鼠除以上改变更加明显外，海马去甲肾上腺素也明显高于对照组；３．铁缺乏非贫血大鼠海马ＣＡ３区神经胶质细胞足突肿胀，细胞器稀疏，缺铁性贫血大鼠神经胶质细胞变性更加严重，并且神经细胞的结构也受到破坏。提示脑组织单胺类神经递质的代谢异常及超微结构的改变可能是铁缺乏大鼠学习记忆障碍的物质基础之一；

The iron deficient rat model was made by feeding them on a low iron content diet(11.9mg/kg)to detect the effect of iron deficiency on their learning and memory ability and its mechanism. It was found that the learning and memory ability was lowed in the early stage of iron deficiency, and it was even lower in anemic stage. Brain iron content, monoamine oxidase activity were decreased in iron deficient nonanemic rats. The levels of NE and 5-HT in cerebral cortex were increased, but 5-HIAA metabolite of 5-HT was decreased in hippocampus in experimental rats. These changes were more significant in anemic rats. Swelling processes and disruption of organellae were found in astrocytes of hippocampal CA3 area in iron deficient nonanemic lats under TEM. In iron deficient anemic rats the processes of astrocytes swelled obviously and organellae disappeared, low density degeneration of the nucleus and disrupted organellae in neurones were also found. These results suggest that even in the early stage of iron deficiency, the learning and memory ability was to be lowered, which may result from the abnormal metabolism of monamine neurotransmitters and the ultrastructural pathological changes in brain of iron deficient rats.