The goal of this study is to induce low-pressure voiding by stimulation and bilateral 1 kHz post-stimulation block of the pudendal nerves. In anesthetized cats, wire hook electrodes were placed on the left and/or right pudendal nerves. Stimulus pulses (30 Hz, 0.2 ms) were applied to one pudendal nerve to induce a reflex bladder contraction and to produce contractions of the external urethral sphincter (EUS). High frequency (1 kHz) biphasic stimulation was applied to block axonal conduction in both pudendal nerves and block EUS activity. In 4 cats, a catheter was inserted into the distal urethra to perfuse and measure the back pressure caused by the EUS contraction. In another 5 cats, a catheter was inserted into the bladder dome and the urethra was left open to allow voiding. The 1 kHz stimulation (30–60 s, 0.5–5 mA) delivered via a wire hook electrode completely blocked pudendal nerve conduction for ≥2 min after terminating the stimulation, i.e., a post-stimulation block. The block gradually disappeared in 6–18 min. The block duration increased with increasing amplitude or duration of the 1 kHz stimulation. Without the 1 kHz block, 30 Hz stimulation alone induced high-pressure (90 cmH₂O) voiding. When combined with the 1 kHz block, the 30 Hz stimulation induced low-pressure (≤50 cmH₂O) voiding with a high voiding efficiency (80%). In summary, a minimally invasive surgical approach might be developed to restore voiding function after spinal cord injury by stimulation and block of the pudendal nerves using lead electrodes.

本研究的目的是通过刺激和双侧 1 kHz 后刺激阴部神经阻滞来诱导低压排尿。在麻醉猫中，线钩电极放置在左侧和/或右侧阴部神经上。对一根阴部神经施加刺激脉冲（30 Hz，0.2 ms）以诱导反射性膀胱收缩并产生尿道外括约肌（EUS）的收缩。高频 (1 kHz) 双相刺激用于阻断阴部神经的轴突传导并阻断 EUS 活动。在 4 只猫中，将导管插入远端尿道以灌注并测量 EUS 收缩引起的背压。在另外 5 只猫中，将一根导管插入膀胱穹窿，尿道保持开放以允许排尿。1 kHz 刺激（30-60 秒，0. 5–5 mA) 通过线钩电极传送，在终止刺激后，即刺激后阻滞，完全阻断阴部神经传导≥2 分钟。该块在 6-18 分钟内逐渐消失。块持续时间随着 1 kHz 刺激的幅度或持续时间的增加而增加。如果没有 1 kHz 阻滞，仅 30 Hz 刺激会引起高压 (90 cmH₂ O) 排尿。当与 1 kHz 块结合时，30 Hz 刺激会诱导低压 (≤50 cmH ₂ O) 排尿，排尿效率高 (80%)。总之，可以开发一种微创手术方法，通过使用铅电极刺激和阻滞阴部神经来恢复脊髓损伤后的排尿功能。