Functional roles of capsaicin-sensitive intrinsic neural circuit in the regulation of esophageal peristalsis in rats: in vivo studies using a novel method.
Functional roles of capsaicin-sensitive intrinsic neural circuit in the regulation of esophageal peristalsis in rats: in vivo studies using a novel method.
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辣椒素敏感的内在神经回路在大鼠食管蠕动调节中的功能作用：使用新方法的体内研究。
DOI：
10.1152/ajpgi.00250.2013
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发表时间：
2014
期刊：
影响因子：
--
通讯作者：
Y.
中科院分区：
文献类型：
--
作者：
Shima;T.;Shiina;T.;Naitou;K.;Nakamori;H.;Shimizu;Y.
由横纹肌层组成的食管中存在发育良好的肌间神经丛，但其在控制蠕动运动中的功能作用仍有待阐明。本研究的目的是阐明由辣椒素敏感的初级传入神经元和内在神经元组成的局部神经反射在食管蠕动中的作用。我们首先设计了一种测量大鼠体内食道蠕动运动的方法。用尿烷麻醉大鼠，记录食管腔内压力和推进的腔内液体体积。在实验系统中，腔内压力刺激引起食管腔内压力的周期性变化，并且始终伴随着腔内液体推进。双侧迷走神经切断术消除了腔内压力和液体推进的变化。这些结果表明，该新方法适合诱导由横纹肌组成的食道蠕动。然后，通过使用该方法，我们检查了局部反射在食管蠕动中的功能作用。为此，我们使用了辣椒素敏感神经元已被破坏的大鼠。接受辣椒素处理的大鼠食管显示出管腔内压力的多相升高，这可能是由于食管肌肉的不协调收缩所致，而在完整的大鼠食管中观察到单相反应。此外，辣椒素敏感神经元的破坏增加了推进的液体体积并降低了启动蠕动的压力阈值。这些结果表明，由辣椒素敏感神经元和内在神经元组成的局部神经反射有助于协调蠕动并抑制食道迷走神经传入的机械感觉功能。
A well-developed myenteric plexus exists in the esophagus composed of striated muscle layers, but its functional role in controlling peristaltic movements remains to be clarified. The purpose of this study was to clarify the role of a local neural reflex consisting of capsaicin-sensitive primary afferent neurons and intrinsic neurons in esophageal peristalsis. We firstly devised a method to measure peristaltic movement of esophagus in vivo in rats. Rats were anesthetized with urethane, and esophageal intraluminal pressure and propelled intraluminal liquid volume were recorded. In the experimental system, an intraluminal pressure stimulus evoked periodic changes in intraluminal pressure of the esophagus, which were consistently accompanied by intraluminal liquid propulsion. Bilateral vagotomy abolished changes in intraluminal pressure as well as liquid propulsion. These results indicate that the novel method is appropriate for inducing peristalsis in the esophagus composed of striated muscles. Then, by using the method, we examined functional roles of the local reflex in esophageal peristalsis. For that purpose, we used rats in which capsaicin-sensitive neurons had been destroyed. The esophagus of capsaicin-treated rats showed a multiphasic rise in intraluminal pressure, which may due to noncoordinated contractions of esophageal muscles, whereas a monophasic response was observed in the intact rat esophagus. In addition, destruction of capsaicin-sensitive neurons increased the propelled liquid volume and lowered the pressure threshold for initiating peristalsis. These results suggest that the local neural reflex consisting of capsaicin-sensitive neurons and intrinsic neurons contributes to coordination of peristalsis and suppresses mechanosensory function of vagal afferents in the esophagus.