Morphological and Electrophysiological Studies on the Formation of the Neural Tract and the Function in the Taste of Frog Chimerae.

青蛙嵌合体神经束形成及其味觉功能的形态学和电生理学研究。

• 批准号: 63540579
• 负责人: YAMASHITA Satoru
• 金额: $ 0.83万
• 依托单位: Kagoshima University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (C)
• 财政年份: 1988
• 资助国家: 日本
• 起止时间: 1988 至 1989
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-63540579/
• 关键词: Taste; African Clawed Toad; Gustatory Center; Glossopharyngeal nerve; Xenopus; Feeding Behavior; Taste Receptor; Chimera

1. Of various agar-soaked gustatory stimuli, Xenopus (X. borealis and X. laevis) accepted L-Pro, L-Trp, and L-Val, while rejected L-Arg, quinine, and HCl. In general, X. borealis was more active and had lower thresholds for these gustatory stimuli than X. laevis. Feeding behavior of chimerae, which were produced by joining a half of an embryo of one species with that of another species, revealed similar behavior to X. laevis, regardless of the location of a half of an embryo of X. borealis.2. Taste buds calculated by staining with Ponceau S were about 300 on the palate, and about 200 on the floor of the mouth, and densely distributed on the inner lip and around the internal nostril. Both the number and location of the taste bud were similar among the two species and chimera. It was confirmed by staining with quinacrine that taste cells originated from an embryo of X. borealis are located ipsilaterally in chimerae. The extent of their contralateral location, however, were left unclear. Morphological tracing of glossopharyngeal nerves with HRP techniques showed that central gustatory neurons are distributed ipsilaterally in the medulla oblongata.3. Major differences in gustatory responses of the glossopharyngeal nerves to 60 gustatory stimuli between the two species were as follow: (1) L-Phe caused significant differences in responses over all concentrations tested, whereas L- and D-Trp, and L- and D-Tyr produced prominent differences in responses within a given concentration range. (2) differences in responses to quinine and strychnine were demonstrated throughout a wide concentration range. (3) among various nucleotides and nucleosides only adenosine produced fairly large responses in X. borealis, but very small responses in X. laevis. It was demonstrated using these substances as key stimuli that glossopharyngeal nerves of chimerae cause species-specific responsiveness during young adult, but that they tend to produce the responsiveness of X. laevis with aging.

1。在各种琼脂浸泡的味觉刺激中，Xenopus（X。Borealis和X. laevis）接受L-Pro，L-Trp和L-Val，而被拒绝的L-Arg，Quinine和HCl。通常，与X. laevis相比，X. borealis更为活跃，对于这些味觉刺激的阈值较低。嵌合体的喂养行为是通过将一种物种与另一种物种的一个胚胎连接在一起的一半胚胎产生的，它揭示了与X. laevis相似的行为，无论X. borealis的胚胎的一半位置如何。通过ponceau S染色计算的味蕾在口感上约为300，在嘴地板上约为200个，密集分布在内唇上和内部鼻孔周围。在这两个物种和嵌合体之间，味蕾的数量和位置相似。通过用奎诺克染色来证实，味道细胞起源于X. borealis的胚胎。在同侧位于嵌合体中。然而，其对侧位置的程度尚不清楚。用HRP技术对全咽神经进行形态学追踪表明，中枢神经元在髓质长圆形的同侧分布。3。舌咽神经对两种物种之间60个味觉刺激的味觉反应的主要差异如下：（1）L-PHE在所有测试浓度的响应中造成了显着差异，而L-和D-TRP以及L和D-TYR在给定浓度范围内产生了显着的反应响应。 （2）在整个浓度范围内都证明了对奎宁和士宁宁的反应差异。 （3）在各种核苷酸和核苷中，仅腺苷在X. borealis中产生相当大的反应，但在X. laevis中的反应非常小。通过这些物质作为关键刺激证明了嵌合脑的全咽神经在年轻人期间会引起物种特异性的反应性，但它​​们倾向于产生X. laevis随老化的反应性。

项目成果

山下智,郡山博司,大平博之,清原貞夫: "アフリカツメガエル2種とそのキメラにみられる味覚神経応答の特異性" Jpn.Symp.Taste and Smell. 23. 115-118 (1989)

Satoshi Yamashita、Hiroshi Koriyama、Hiroyuki Ohira、Sadao Kiyohara：“在两种爪蟾及其嵌合体中观察到的味觉神经反应的特异性”Jpn.Symp.Taste and Smell 23. 115-118 (1989)。

Satoru Yamashita: "Chemospecificities of gustatory responses of two species of Xenopus and the chimera." Jpn. Symp. Taste and Smell. 23. 115-118 (1989)

Satoru Yamashita：“两种爪蟾和嵌合体的味觉反应的化学特异性。”