Singh S C
Acta Neuropathol. 1977 Oct 10;40(2):111-6. doi: 10.1007/BF00688698.
Ectopic neurons have been detected in the hippocampus of postnatal hooded rats aged 5-24 days. These rats were exposed to methylazoxymethanol acetate (MAMac) during foetal development by injecting the mother rats with this neurotoxin. At birth, the hippocampus of rats exposed to MAMac showed a normal cytoarchitecture; ectopic neurones became prevalent from 5 days onwards. These ectopic neurones were restricted to subfields CA 1-2 of Ammon's horn, and evidence is presented which suggests that these ectopic sites are formed by neuronal emigration from stratum pyramidale. Ectopic neurones have been shown to occur in genetic abnormalities of man, and in the mutant mouse 'reeler'. MAMac is a powerful methylating agent especially for guanine which is present in DNA and RNA. It is postulated that viable cells with an altered DNA-RNA state may in some way be predisposed to the formation of ectopic cell clusters after a latent period. The movement of neurones from stratum pyramidale provides a convenient animal model for investigating the mechanisms by which ectopic neuronal sites are formed by abnormal migratory patterns.
在出生后5至24天的带帽大鼠海马中检测到异位神经元。这些大鼠在胎儿发育期间通过给母鼠注射神经毒素乙酸甲基偶氮甲醇（MAMac）而暴露于该毒素。出生时，暴露于MAMac的大鼠海马显示出正常的细胞结构；从5天起异位神经元变得普遍。这些异位神经元局限于海马角的CA 1-2亚区，并且有证据表明这些异位位点是由锥体层的神经元迁移形成的。异位神经元已被证明在人类的基因异常以及突变小鼠“reeler”中出现。MAMac是一种强大的甲基化剂，尤其对存在于DNA和RNA中的鸟嘌呤具有甲基化作用。据推测，具有改变的DNA-RNA状态的存活细胞可能在某种程度上在潜伏期后易于形成异位细胞簇。来自锥体层的神经元移动为研究异位神经元位点通过异常迁移模式形成的机制提供了一个便利的动物模型。
