Physiology, Pharmacology and Neuroscience, University of Bristol, Bristol, UK.
Neuromodulation. 2019 Aug;22(6):703-708. doi: 10.1111/ner.12928. Epub 2019 Feb 20.
High-frequency (kHz) stimulation of preganglionic pelvic nerve afferents can inhibit voiding in both anesthetized and conscious rats. The afferents travel via the S1 sacral nerve root, which is easier to access than the distal pelvic nerve fibers within the abdominal cavity. We therefore investigated whether voiding could be inhibited by high-frequency stimulation at S1 and how this compared to distal pelvic nerve stimulation.
Urethane-anesthetized rats were instrumented to record bladder pressure and abdominal wall electromyogram and to stimulate the distal preganglionic pelvic nerve bundle and S1 sacral root. Saline was infused continuously into the bladder to evoke repeated voiding. Stimulation was initiated within 1-2 sec of the onset of the steep rise in bladder pressure signaling an imminent void.
In six rats, stimulation of the distal pelvic nerve bundle (1-3 kHz sinusoidal waveform 1 mA, 60 sec) supressed the occurrence of an imminent void. Voiding resumed within 70 ± 13.0 sec (mean ± SEM) of stopping stimulation. Stimulation (using the same parameters) of the S1 root at the level of the sacral foramen suppressed voiding for the entire stimulation period in three rats and deferred voiding for 35-56 sec (mean 44.0 ± 3.2 sec) in the remaining three. Stimulation at either site when the bladder was approximately half full, as estimated from previous intervoid intervals, had no effect on voiding.
This preliminary study provides proof-of-concept for the sacral root as an accessible target for high-frequency stimulation that may be developed as an "on demand" neuromodulation paradigm to suppress unwanted urinary voids.
The authors reported no conflict of interest.
高频（kHz）刺激节前盆神经传入纤维可以抑制麻醉和清醒大鼠的排尿。传入纤维通过 S1 骶神经根传递，这比腹腔内远端盆神经纤维更容易接近。因此，我们研究了高频刺激 S1 是否可以抑制排尿，以及与远端盆神经刺激相比如何。
用乌拉坦麻醉大鼠，记录膀胱压力和腹壁肌电图，并刺激远端节前盆神经束和 S1 骶神经根。盐水连续注入膀胱以诱发重复排尿。刺激在膀胱压力急剧升高的 1-2 秒内开始，提示即将排尿。
在六只大鼠中，刺激远端盆神经束（1-3 kHz 正弦波，1 mA，60 秒）抑制了即将发生的排尿。停止刺激后，排尿在 70±13.0 秒（平均值±SEM）内恢复。在三只大鼠中，在骶孔水平刺激 S1 根（使用相同参数）可在整个刺激期间抑制排尿，在其余三只大鼠中，可推迟排尿 35-56 秒（平均值 44.0±3.2 秒）。当膀胱大约是上次排尿间隔的一半时，在这两个部位刺激（根据之前的两次排尿间隔估计）对排尿没有影响。
这项初步研究为高频刺激骶神经根提供了概念验证，作为一种“按需”神经调节范式，可能被开发用于抑制不必要的尿排空。
作者报告没有利益冲突。
