Central regulation of the pharyngeal and upper esophageal reflexes during swallowing in the Japanese eel
Central regulation of the pharyngeal and upper esophageal reflexes during swallowing in the Japanese eel
复制标题
日本鳗鱼吞咽过程中咽部和上食管反射的中枢调节
DOI：
10.1007/s00359-009-0498-4
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发表时间：
2010
期刊：
影响因子：
--
通讯作者：
Mukuda Takao and Ando Masaaki
中科院分区：
文献类型：
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作者：
Nojima T;Kimura K-I;Koganezawa M;Yamamoto D.;Mukuda Takao and Ando Masaaki
本研究探讨了鳗鱼吞咽过程中咽反射和食道上段反射的调节。通过肌肉逆行追踪，上食管括约肌（UES）运动神经元位于舌咽-迷走神经运动复合体（mGVC）中段的尾侧。相反，支配咽壁的运动神经元位于mGVC内侧。迷走神经中的感觉咽纤维终止于内脏感觉柱（cVSC）的尾侧区。使用离体脑，我们记录了51个自发活动的神经元内mGVC。这些神经元可分为节律性（n=8）和连续性（n=43）放电单位。节律性放电神经元似乎被限制在内侧，而连续放电神经元被发现尾侧内mGVC。刺激cVSC可激活节律性放电神经元。相比之下，cVSC的刺激抑制了大多数但不是所有连续放电神经元的放电。在38个神经元中有17个被哌唑嗪阻断。育亨宾还能阻断cVSC对5个哌唑嗪敏感神经元的抑制作用。我们认为，cVSC中的神经元抑制持续放电的运动神经元以放松UES，同时刺激节律放电的神经元以收缩咽。
We investigated the regulation of the pharyngeal and upper esophageal reflexes during swallowing in eel. By retrograde tracing from the muscles, the motoneurons of the upper esophageal sphincter (UES) were located caudally within the mid-region of the glossopharyngeal-vagal motor complex (mGVC). In contrast, the motoneurons innervating the pharyngeal wall were localized medially within mGVC. Sensory pharyngeal fibers in the vagal nerve terminated in the caudal region of the viscerosensory column (cVSC). Using the isolated brain, we recorded 51 spontaneously active neurons within mGVC. These neurons could be divided into rhythmically (n=8) and continuously (n=43) firing units. The rhythmically firing neurons seemed to be restricted medially, whereas the continuously firing neurons were found caudally within mGVC. The rhythmically firing neurons were activated by the stimulation of the cVSC. In contrast, the stimulation of the cVSC inhibited firing of most, but not all the continuously firing neurons. The inhibitory effect was blocked by prazosin in 17 out of 38 neurons. Yohimbine also blocked the cVSC-induced inhibition in five of prazosin-sensitive neurons. We suggest that the neurons in cVSC inhibit the continuously firing motoneurons to relax the UES and stimulate the rhythmically firing neurons to constrict the pharynx simultaneously.