Initial innervation of embryonic rat tongue and developing taste papillae: nerves follow distinctive and spatially restricted pathways.
Initial innervation of embryonic rat tongue and developing taste papillae: nerves follow distinctive and spatially restricted pathways.
复制标题
胚胎大鼠舌头的初始神经支配和味觉乳头的发育：神经遵循独特且空间受限的路径。
DOI：
10.1159/000148006
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发表时间：
1997
期刊：
影响因子：
--
通讯作者：
Mistretta,CM
中科院分区：
文献类型：
--
作者：
Mbiene,JP;Mistretta,CM
大鼠的舌有来自四条脑神经的广泛而复杂的神经。然而，这些神经进入胚胎舌体的确切发育时间进程和空间路线尚不清楚，尽管这一知识对于研究调节舌味器官、味觉乳头和常驻味蕾的发育和神经支配的机制至关重要。我们确定了发育中的舌和乳头中神经的初始空间轨迹，并检验了感觉神经首先均匀地支配舌头，然后收缩到更密集地支配乳头和味蕾的假说。用抗GAP-43和神经丝的抗体标记孕11-16天(E11-E16)大鼠胚胎头部的神经纤维。追踪并重建连续矢状面，以追踪每条神经的路径。在E11大鼠，膝状神经节、三叉神经节和岩神经节被标记，纤维离开神经节并向各自的颧弓延伸。在胚胎13岁时，当发育中的舌仍是一组组织肿胀时，脊索/舌神经、舌下神经和岩神经从不同的位置接近舌肿。在这一阶段，只有脊索/舌根进入舌根。在E14和E15，发育良好的舌被所有四条脑神经支配。然而，神经在舌内保持着独特的入口点和相对有限的间充质区域，在共同的早期通路中并不相互跟随。此外，脊索/舌神经和舌咽神经并没有为味觉乳头的发育建立明显的前置模式，而是被发育中的乳头所吸引，与周围的上皮相比，在EL5时，乳头变得非常密集。为了实现这种密集的乳头神经支配，感觉神经最初并不以均匀的方式神经支配舌头，随后纤维回缩和/或广泛重定向到味觉器官。研究结果为舌神经发育提供了一套工作原理。入口点和最初的神经通路从舌头形成的时间到形态发生都受到限制，这表明每条神经都有独特的语言领土。因此，感觉神经和运动神经相互独立地分布，对舌前和舌后的感觉神经支配仍然是离散的。对于味觉器官的神经支配，味觉乳头不是由预先形成的神经分布引起的。事实上，乳头可能会吸引密集的感觉神经，因为无论是脊索/舌神经还是舌咽神经，都不会均匀地生长到舌上皮，然后重新分布到单个乳头。
The rat tongue has an extensive, complex innervation from four cranial nerves. However, the precise developmental time course and spatial routes of these nerves into the embryonic tongue are not known, although this knowledge is crucial for studying mechanisms that regulate development and innervation of the lingual taste organs, gustatory papillae and resident taste buds. We determined the initial spatial course of nerves in the developing tongue and papillae, and tested the hypothesis that sensory nerves first innervate the tongue homogeneously and then retract to more densely innervate papillae and taste buds. Antibodies to GAP-43 and neurofilaments were used to label nerve fibers in rat embryo heads from gestational day 11 through 16 (E11-E16). Serial sagittal sections were traced and reconstructed to follow paths of each nerve. In E11 rat, geniculate, trigeminal and petrosal ganglia were labeled and fibers left the ganglia and extended toward respective branchial arches. At E13 when the developing tongue is still a set of tissue swellings, the combined chorda/lingual, hypoglossal and petrosal nerves approached the lingual swellings from separate positions. Only the chorda/lingual entered the tongue base at this stage. At E14 and E15, the well-developed tongue was innervated by all four cranial nerves. However, the nerves maintained distinctive entry points and relatively restricted mesenchymal territories within the tongue, and did not follow one another in common early pathways. Furthermore, the chorda/lingual and glossopharyngeal nerves did not set up an obvious prepattern for gustatory papilla development, but rather seemed attracted to developing papillae which became very densely innervated compared to surrounding epithelium at El5. To effect this dense papilla innervation, sensory nerves did not first innervate the tongue in a homogeneous manner with subsequent retraction and/or extensive redirection of fibers into the taste organs. Results contribute to a set of working principles for development of tongue innervation. Points of entry and initial neural pathways are restricted from time of tongue formation through morphogenesis, suggesting distinctive lingual territories for each nerve. Thus, sensory and motor nerves distribute independently of each other, and sensory innervation to anterior and posterior tongue remains discrete. For taste organ innervation, gustatory papillae are not induced by a prepatterned nerve distribution. In fact, papillae might attract dense sensory innervation because neither chorda/lingual nor glossopharyngeal nerve grows homogeneously to the lingual epithelium and then redistributes to individual papillae.