Plasticity of auditory medullary-midbrain connectivity across metamorphic development in the bullfrog, Rana catesbeiana.
Plasticity of auditory medullary-midbrain connectivity across metamorphic development in the bullfrog, Rana catesbeiana.
复制标题
牛蛙变态发育过程中听觉髓质-中脑连接的可塑性。
DOI：
10.1159/000095027
复制
发表时间：
2007
期刊：
影响因子：
--
通讯作者：
Simmons,AndreaMegela
中科院分区：
文献类型：
--
作者：
Horowitz,SethS;Chapman,JudithA;Simmons,AndreaMegela
根据示踪剂从上级橄榄核（SON）和枕丘（TS）的顺行，逆行和双向运输的模式，我们报告牛蛙（Rana catesbeiana）的脑干连接在变态发育过程中的解剖学变化。在幼虫发育的早期和晚期阶段（Gosner阶段25-37），顺行或双向示踪剂注入SON在对侧SON和同侧TS中产生末端/纤维标记。在第38-41阶段（聋期）之间，在这些靶细胞核中仅可见稀疏的或看不到末端/纤维标记。在变态高潮（阶段42-46），终端/纤维标签重新出现在对侧SON和同侧TS，现在也在对侧TS。逆行示踪剂注射到SON未能标记细胞体的同侧TS在耳聋期间的动物，反映了先前报道的失败的逆行运输从TS同侧SON在这个发展的时间。由于SON运输的结果，在幼虫后期，双侧延髓背核和前庭外侧核中出现了双侧胞体标记，而在对侧TS中出现胞体标记是在高潮期。在所有的幼虫阶段，注射到SON产生顺行和逆行的标签在内侧前庭核双边。这些数据表明，在某些途径的解剖稳定性和可塑性在其他幼虫的发展过程中，最戏剧性的变化发生在失聪期间和变质高潮。动物在变质顶极显示模式的连接类似的小蛙和成年人，表明成熟的中央解剖基板在空气中的听觉顶极。
On the basis of patterns of anterograde, retrograde, and bi-directional transport of tracers from both the superior olivary nucleus (SON) and the torus semicircularis (TS), we report anatomical changes in brainstem connectivity across metamorphic development in the bullfrog, Rana catesbeiana. In early and late stages of larval development (Gosner stages 25–37), anterograde or bi-directional tracers injected into the SON produce terminal/fiber label in the contralateral SON and in the ipsilateral TS. Between stages 38–41 (deaf period), only sparse or no terminal/fiber label is visible in these target nuclei. During metamorphic climax (stages 42–46), terminal/fiber label reappears in both the contralateral SON and in the ipsilateral TS, and now also in the contralateral TS. Injections of retrograde tracers into the SON fail to label cell bodies in the ipsilateral TS in deaf period animals, mirroring the previously-reported failure of retrograde transport from the TS to the ipsilateral SON during this developmental time. Bilateral cell body label emerges in the dorsal medullary nucleus and the lateral vestibular nucleus bilaterally as a result of SON transport during the late larval period, while cell body label in the contralateral TS emerges during climax. At all larval stages, injections into the SON produce anterograde and retrograde label in the medial vestibular nucleus bilaterally. These data show anatomical stability in some pathways and plasticity in others during larval development, with the most dramatic changes occurring during the deaf period and metamorphic climax. Animals in metamorphic climax show patterns of connectivity similar to that of froglets and adults, indicating the maturation during climax of central anatomical substrates for hearing in air.