Does the capsaicin-sensitive local neural circuit constitutively regulate vagally evoked esophageal striated muscle contraction in rats?

作者：Shima Takeshi^*; Shiina Takahiko; Naitou Kiyotada; Nakamori Hiroyuki; Sano Yuuki; Shimizu Yasutake

来源：Journal of Physiological Sciences, 2016, 66(2): 105-111.

DOI：10.1007/s12576-015-0401-8

• Capsaicin-sensitive neuron
• Enteric neuron
• Esophagus
• Striated muscle
• Vagus

To determine whether a capsaicin-sensitive local neural circuit constitutively modulates vagal neuromuscular transmission in the esophageal striated muscle or whether the neural circuit operates in a stimulus-dependent manner, we compared the motility of esophageal preparations isolated from intact rats with those in which capsaicin-sensitive neurons had been destroyed. Electrical stimulation of the vagus nerve trunk evoked contractile responses in the esophagus isolated from a capsaicin-treated rat in a manner similar to those in the esophagus from a control rat. No obvious differences were observed in the inhibitory effects of D-tubocurarine on intact and capsaicin-treated rat esophageal motility. Destruction of the capsaicin-sensitive neurons did not significantly affect latency, time to peak and duration of a vagally evoked twitch-like contraction. These findings indicate that the capsaicin-sensitive neural circuit does not operate constitutively but rather is activated in response to an applied stimulus.

• 出版日期2016-3