Tai Changfeng, Wang Jicheng, Wang Xianchun, de Groat William C, Roppolo James R
Department of Pharmacology, University of Pittsburgh, Pittsburgh, Pennsylvania.
Neurourol Urodyn. 2007;26(4):570-577. doi: 10.1002/nau.20374.
To investigate pudendal-to-bladder spinal reflexes in chronic spinal cord injured (SCI) cats induced by electrical stimulation of the pudendal nerve.
Bladder inhibition or voiding induced by pudendal nerve stimulation at different frequencies (3 or 20 Hz) was studied in three female, chronic SCI cats under alpha-chloralose anesthesia.
Voiding induced by a slow infusion (2-4 ml/min) of saline into the bladder was very inefficient (voiding efficiency=7.3%+/-0.9%). Pudendal nerve stimulation at 3 Hz applied during the slow infusion inhibited reflex bladder activity, and significantly increased bladder capacity to 147.2+/-6.1% of its control capacity. When the 3-Hz stimulation was terminated, voiding rapidly occurred and the voiding efficiency was increased to 25.4+/-6.1%, but residual bladder volume was not reduced. Pudendal nerve stimulation at 20 Hz induced large bladder contractions, but failed to induce voiding during the stimulation due to the direct activation of the motor pathway to the external urethral sphincter. However, intermittent pudendal nerve stimulation at 20 Hz induced post-stimulus voiding with 78.3+/-12.1% voiding efficiency. The voiding pressures (39.3+/-6.2 cmH2O) induced by the intermittent pudendal nerve stimulation were higher than the voiding pressures (23.1+/-1.7 cmH2O) induced by bladder distension. The flow rate during post-stimulus voiding induced by the intermittent pudendal nerve stimulation was significantly higher (0.93+/-0.04 ml/sec) than during voiding induced by bladder distension (0.23+/-0.07 ml/sec).
This study indicates that a neural prosthetic device based on pudendal nerve stimulation might be developed to restore micturition function for people with SCI.
研究电刺激阴部神经诱发慢性脊髓损伤（SCI）猫的阴部-膀胱脊髓反射。
在α-氯醛糖麻醉下，对三只慢性SCI雌性猫进行研究，观察不同频率（3或20Hz）阴部神经刺激诱发的膀胱抑制或排尿情况。
以2-4ml/分钟的速度缓慢向膀胱内注入生理盐水诱发的排尿效率很低（排尿效率=7.3%±0.9%）。在缓慢注入生理盐水过程中施加3Hz的阴部神经刺激可抑制反射性膀胱活动，并使膀胱容量显著增加至对照容量的147.2%±6.1%。当3Hz刺激终止时，迅速出现排尿，排尿效率提高到25.4%±6.1%，但膀胱残余尿量未减少。20Hz的阴部神经刺激可诱发膀胱大幅收缩，但由于直接激活了尿道外括约肌的运动通路，在刺激期间未能诱发排尿。然而，20Hz的间歇性阴部神经刺激可诱发刺激后排尿，排尿效率为78.3%±12.1%。间歇性阴部神经刺激诱发的排尿压力（39.3±6.2cmH2O）高于膀胱扩张诱发的排尿压力（23.1±1.7cmH2O）。间歇性阴部神经刺激诱发的刺激后排尿流速（0.93±0.04ml/秒）显著高于膀胱扩张诱发的排尿流速（0.23±0.07ml/秒）。
本研究表明，基于阴部神经刺激的神经假体装置可能被开发出来，用于恢复SCI患者的排尿功能。
