Matsufuji H
Department of Surgery, School of Medicine, Keio University.
Nihon Heikatsukin Gakkai Zasshi. 1990 Aug;26(4):199-218. doi: 10.1540/jsmr1965.26.199.
Responses of isolated muscle strips from the rat and the dog internal anal sphincter (IAS) to drugs and electrical field stimulation (EFS) were investigated in vitro for the purpose of clarifying a manner of neural control of IAS. Also, responses of muscle strips from IAS of the patients with Hirschsprung's disease were compared with those of muscle strips from human control IAS. Muscle strips from the dog and human IAS as normal control showed contractions to norepinephrine (NE), which were abolished in the presence of phentolamine and relaxations to isoproterenol. EFS (less than 1 msec) induced relaxations of the muscle strips. These responses to EFS were not affected by either one of phentolamine, propranolol and atropine but were inhibited by tetrodotoxin. Muscle strips from IAS in Hirschsprung's disease contracted to both NE and EFS, the responses of which were abolished in the presence of phentolamine. But no relaxation to EFS of muscle strips from IAS in Hirschsprung's disease was observed. These findings revealed that normal IAS is pharmacologically innervated by alpha-adrenergic excitatory nerve, beta-adrenergic inhibitory nerve and non-adrenergic, non-cholinergic inhibitory nerve and suggested that IAS in Hirschsprung's disease is also affected by alpha-adrenergic excitatory nerve but inhibitory neural control is absent.
为阐明肛门内括约肌（IAS）的神经控制方式，对大鼠和犬的离体肛门内括约肌肌条对药物和电场刺激（EFS）的反应进行了体外研究。此外，还将先天性巨结肠病患者的IAS肌条反应与正常对照者的IAS肌条反应进行了比较。作为正常对照的犬和人IAS肌条对去甲肾上腺素（NE）表现出收缩反应，在酚妥拉明存在时收缩反应消失，对异丙肾上腺素表现出舒张反应。EFS（小于1毫秒）可诱导肌条舒张。这些对EFS的反应不受酚妥拉明、普萘洛尔和阿托品中任何一种的影响，但被河豚毒素抑制。先天性巨结肠病患者的IAS肌条对NE和EFS均有收缩反应，在酚妥拉明存在时反应消失。但未观察到先天性巨结肠病患者的IAS肌条对EFS的舒张反应。这些发现表明，正常的IAS在药理学上受α-肾上腺素能兴奋性神经、β-肾上腺素能抑制性神经和非肾上腺素能、非胆碱能抑制性神经支配，并提示先天性巨结肠病患者的IAS也受α-肾上腺素能兴奋性神经影响，但缺乏抑制性神经控制。
