Speakman C T, Hoyle C H, Kamm M A, Henry M M, Nicholls R J, Burnstock G
Sir Alan Parks Physiology Unit, St. Mark's Hospital, London, UK.
Br J Surg. 1990 Dec;77(12):1342-4. doi: 10.1002/bjs.1800771208.
There is histological and functional evidence that the internal anal sphincter is abnormal in patients with idiopathic faecal incontinence. The in vitro responsiveness of the internal anal sphincter to noradrenaline (an important sympathetic neurotransmitter) and electrical field stimulation (known to stimulate the intrinsic innervation) has been studied. Muscle strips from eight patients with incontinence undergoing postanal repair and five controls undergoing resection for low rectal carcinoma were studied. The contraction-response curves for noradrenaline were significantly different, and the EC50, the concentration required to produce 50 per cent of maximum contraction, was higher in incontinent patients (P less than 0.001). Electrical field stimulation produced initial contractions in four of the control group which were blocked by phentolamine. This contraction was not present in the incontinent patients (P less than 0.01). These results indicate an abnormality in the adrenergic innervation of the internal anal sphincter in patients with idiopathic faecal incontinence.
有组织学和功能学证据表明，特发性大便失禁患者的肛门内括约肌存在异常。已对肛门内括约肌对去甲肾上腺素（一种重要的交感神经递质）和电场刺激（已知可刺激内在神经支配）的体外反应性进行了研究。研究了8例接受肛门后修复术的失禁患者和5例因低位直肠癌接受切除术的对照组患者的肌肉条。去甲肾上腺素的收缩反应曲线有显著差异，产生最大收缩50%所需的浓度即半数有效浓度（EC50）在失禁患者中更高（P<0.001）。电场刺激在对照组的4例患者中产生了初始收缩，这些收缩被酚妥拉明阻断。失禁患者中不存在这种收缩（P<0.01）。这些结果表明，特发性大便失禁患者的肛门内括约肌肾上腺素能神经支配存在异常。
