Straka Hans, Baker Robert, Gilland Edwin
Department of Physiology, Ludwig-Maximilians-Universität München, München, Germany.
Brain Res Bull. 2002;57(3-4):301-5. doi: 10.1016/s0361-9230(01)00670-0.
The segmental organization of cranial nerve efferent, vestibular, and precerebellar neurons of larval ranid frogs is essentially retained in adult frogs, indicating the absence of any substantial postembryonic longitudinal migration of hindbrain neurons in this group. Comparison of the rhombomeric organization of vestibulomotor and branchiomotor pathways across different species suggests that the frog hindbrain blueprint is common to most vertebrates. The unique segmental stability seen in frogs can be used to create a quantitative stereotactic map of the adult brain that mirrors the embryonic and larval rhombomeric framework. Such a map allows the large number of physiologically identified hindbrain neurons in adult frogs to be linked with their underlying genetic specification. Transgenic reporters and antisense knockdown of gene activities suspected of having necessary functions in patterning neurons within specific rhombomeres may allow direct testing of the proposed map.
蝌蚪期蛙类的脑神经传出神经元、前庭神经元和小脑前神经元的节段组织在成年蛙中基本得以保留，这表明该类群中后脑神经元在胚胎后期没有发生实质性的纵向迁移。对不同物种前庭运动和鳃运动通路的菱脑节组织进行比较表明，蛙类的后脑蓝图在大多数脊椎动物中是共有的。蛙类中独特的节段稳定性可用于创建成年脑的定量立体定位图谱，该图谱反映了胚胎期和蝌蚪期的菱脑节框架。这样的图谱能够将成年蛙中大量经生理鉴定的后脑神经元与其潜在的基因特征联系起来。对于怀疑在特定菱脑节内神经元模式形成中具有必要功能的基因活动，利用转基因报告基因和反义基因敲低技术，或许可以对所提出的图谱进行直接验证。
