Jolesz F A, Ruenzel P W, Henneman E
Department of Radiology, Harvard Medical School, Boston, MA.
Arch Neurol. 1988 Jan;45(1):38-40. doi: 10.1001/archneur.1988.00520250044018.
When the spinal motoneurons innervating the external sphincter of the urethra cannot be inhibited voluntarily due to lesions of the spinal cord, the normal capacity to relax this physiologic valve during micturition is lost. Even if contractions of the bladder occur, urinary outflow may be completely blocked at the sphincter, leading to distention of the bladder and the risk of urinary infection. A method is described for controllably relaxing the sphincter, which permits free outflow of urine in paraplegic cats. One pudendal nerve is sectioned, paralyzing half of the sphincter, but leaving the experimental animals entirely continent. The motoneurons supplying the other half of the sphincter are inhibited by means of spinal reflexes, eliminating active resistance to urethral flow. The simplicity of this approach suggests that it may prove equally effective in human paraplegia.
当支配尿道外括约肌的脊髓运动神经元因脊髓损伤而无法被自主抑制时，在排尿过程中放松这个生理瓣膜的正常能力就会丧失。即使膀胱发生收缩，尿液流出也可能在括约肌处完全受阻，导致膀胱扩张及泌尿系统感染风险。本文描述了一种可控放松括约肌的方法，该方法可使截瘫猫的尿液自由流出。切断一条阴部神经，使一半的括约肌麻痹，但实验动物仍能完全控制排尿。通过脊髓反射抑制供应另一半括约肌的运动神经元，消除对尿道尿液流动的主动阻力。这种方法的简易性表明，它可能对人类截瘫同样有效。
