Taste-responsive neurons in the nucleus of the solitary tract receive gustatory information from both sides of the tongue in the hamster.
Taste-responsive neurons in the nucleus of the solitary tract receive gustatory information from both sides of the tongue in the hamster.
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仓鼠孤束核中的味觉反应神经元从舌头两侧接收味觉信息。
DOI：
10.1152/ajpregu.00791.2007
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发表时间：
2008
期刊：
影响因子：
--
通讯作者：
Cho,YoungK
中科院分区：
文献类型：
--
作者：
Li,Cheng-Shu;Mao,Limin;Cho,YoungK
舌前部左右两侧的味觉感受器受鼓索 (CT) 纤维支配，这些纤维将味觉信息传递到同侧孤束核 (NST)。尽管前舌对于味觉至关重要，但单侧 CT 神经损伤的患者通常报告其味觉体验没有主观变化。解释味觉恒定性的现行理论是“抑制的释放”，该理论假设在 NST 内，来自 CT 和舌咽神经的输入之间存在抑制性相互作用，并且来自 CT 的味觉信息的损失通过对舌咽神经输入的抑制的释放来补偿。然而，从未在啮齿类动物中研究过通过舌头另一侧的味觉输入进行补偿的可能性。我们记录了 NST 中 95 个味觉反应神经元，并检查了它们对对侧 CT 刺激的反应。 46 个细胞被激活，大部分具有兴奋性反应（42 个细胞）。将利多卡因微量注射到对侧 NST 中可阻断由对侧 CT 刺激诱导的 NST 细胞的激活，但不受对侧臂旁核 (PbN) 麻醉的影响。此外，将利多卡因微注射到对侧 NST 后，被对侧 CT 刺激激活的 NST 细胞表现出对味觉刺激的反应性降低。这些结果表明，NST 中近一半的味觉神经元接收来自舌头两侧的味觉信息。双边 NST 之间的这种“串扰”也可能有助于“口味恒定”。
Taste receptors on the left and right sides of the anterior tongue are innervated by chorda tympani (CT) fibers, which carry taste information to the ipsilateral nucleus of the solitary tract (NST). Although the anterior tongue is essential for taste, patients with unilateral CT nerve damage often report no subjective change in their taste experience. The standing theory that explains the taste constancy is the “release of inhibition”, which hypothesizes that within the NST there are inhibitory interactions between inputs from the CT and glossopharyngeal nerves and that the loss of taste information from the CT is compensated by a release of inhibition on the glossopharyngeal nerve input. However, the possibility of compensation by taste input from the other side of the tongue has never been investigated in rodents. We recorded from 95 taste-responsive neurons in the NST and examined their responsiveness to stimulation of the contralateral CT. Forty-six cells were activated, mostly with excitatory responses (42 cells). Activation of NST cells induced by contralateral CT stimulation was blocked by microinjection of lidocaine into the contralateral NST but was not affected by anesthetization of the contralateral parabrachial nuclei (PbN). In addition, the NST cells that were activated by contralateral CT stimulation showed reduced responsiveness to taste stimulation after microinjection of lidocaine into the contralateral NST. These results demonstrate that nearly half of the taste neurons in the NST receive gustatory information from both sides of the tongue. This “cross talk” between bilateral NST may also contribute to the “taste constancy”.