Bladder, Urethra and Anal Sphincter Reinnervation

 描述(由申请人提供)：我们的长期目标是开发手术方法，以重新支配下运动神经元受损的膀胱、尿路和肛门括约肌。我们已经非常成功地使用犬模型来证明躯体神经可以重新路由到盆腔神经的前膀胱支(在盆丛和膀胱顶之间)，以重新支配膀胱肌。我们发现，电刺激这些被转移的神经可以增加逼尿肌压力并诱导膀胱排空，并通过逆行追踪方法证实了这些重新布线的神经的再生。4、25、44-46然而，在这些手术被广泛接受并应用于患有下运动神经元受损的膀胱功能障碍的人类患者之前，我们需要在这个动物模型中回答一些临床相关的问题。临床上最相关的总体问题是，这种神经再支配是否真的改善了清醒动物的存储和排空功能？ 这将在下面的目标中通过使用植入物进行尿动力学研究来解决 在术后6个月的观察期内，对非麻醉动物进行射频微刺激器和功能性电刺激(FES)25、45、46次，以恢复其膀胱和尿道括约肌的神经功能。在安乐死中，将使用电生理学、药理学、神经解剖学和神经生物学的方法来探索对神经再支配的影响。 目的1-确定闭孔神经移位和闭孔神经再支配膀胱术 股神经分支移位可恢复尿路和肛门括约肌的排空和控制功能。我们发现，主要运动供体神经(股神经分支)的移植提供了比混合感觉和运动神经(GFN)更优越的膀胱神经再支配。25我们还发现，可以通过转移股神经的运动分支来重新支配阴部神经。15，47我们还没有在同一动物中重新支配膀胱、尿路和肛门括约肌，这对于人类患者恢复排尿功能、大便和尿控是非常重要的。闭孔神经和股神经一样，是一种主要的运动神经，它的自然路径非常 靠近骨盆神经丛。动物将通过双侧横断L7和所有脊椎尾侧至L7的根来分散。闭孔神经将被转移到双侧 骨盆神经的前膀胱支(OBNT-to-PN)和股神经的分支在阴部神经从阴部(Alcock‘s)管出来时，将被转移到双侧的阴部神经(FNT-to-PudN)。每6个月行一次非麻醉尿流动力学检查，其中一半接受植入射频微刺激器的闭孔肌和股神经分支功能电刺激，监测神经刺激的恢复情况，诱发逼尿肌、尿路和肛门括约肌压力，6个月后进行末梢检查。 目标2-确定膀胱、尿路和肛门括约肌是否仍有能力 在长达一年的长期权力下放后重新紧张起来。我们在5只狗身上发现，去中心化后4.5±0.9个月，刺激骶神经根或脊髓节段并没有增加逼尿肌的压力，证明去中心化。然而，刺激盆神经前膀胱支(盆丛和膀胱顶之间)会增加5只去中心化动物的逼尿肌压力。25我们还证明了去中心化后1个月和3个月时，可以通过生殖股神经移位术(GFNT)重新支配膀胱。46去中心化后膀胱保持能够再神经支配的时间越长，这种入路对长期软性膀胱麻痹的人类患者就越可行。膀胱将是分散的，如目标1所述。与射频微刺激器接口的袖带电极将被放置在盆神经的前膀胱支和阴部神经支上，当它们从阴部管中冒出时，这些动物的一部分。神经刺激对逼尿肌、尿道和肛门括约肌压力的影响将从分散后3-4周开始，持续到6或12个月，每月测定一次。OBNT-to-PN和FNT-to-PudN将在分散后6个月和12个月在不同的动物组中进行。这些组将与植入相同射频微刺激器的假分散动物进行比较。这一模型将确定远端盆丛/神经节-膀胱、尿路和肛门括约肌回路在去中心化后是否仍然有效并能够重新支配长达1年的时间，以指导外科医生在马尾神经损伤后考虑进行类似的神经移位。 这些拟议的研究旨在回答一些问题，这些手术程序将被广泛接受并应用于患有下运动神经元损伤的膀胱功能障碍的人类患者；这一组包括下脊髓损伤、脊柱损伤的患者。 脊柱裂、骨盆或骶骨骨折，以及下腰神经和骶神经的其他神经损伤。

 DESCRIPTION (provided by applicant): Our long-term goals are to develop surgical approaches to reinnervate the lower motor neuron-lesioned urinary bladder, urethra and anal sphincter. We have been highly successful in using a canine model to prove that somatic nerves can be rerouted to the anterior vesical branch of the pelvic nerve (between the pelvic plexus and the bladder dome) to reinnervate the bladder muscle. We found that electrical stimulation of these transferred nerves can increase detrusor pressure and induce bladder emptying, and confirmed regrowth of these rerouted nerves using retrograde tracing methods.4, 25, 44-46 Nevertheless, a number of clinically relevant questions remain that we need to answer in this animal model before these surgical procedures are widely accepted and applied to human patients with lower motor neuron lesioned bladder dysfunction. The most clinically relevant overall question is does this reinnervation actually improve storage and emptying function in the awake animal? This will be addressed in the aims below by performing urodynamic studies, using implanted radiofrequency (RF) micro-stimulators and functional electrical stimulation (FES) of the rerouted nerves,25, 45, 46 on non-anesthetized animals at regular intervals as their bladders and urethral sphincters become reinnervated during a 6-month post-operative observation period. At euthanasia, the effects on reinnervation will be explored using electrophysiological, pharmacological, neuroanatomical, and neurobiological methods. Aim 1 - To determine whether reinnervation of the bladder by obturator nerve transfer and reinnervation of the urethral and anal sphincters by transfer of femoral nerve branches provides return of both continence and emptying function. We found that transfer of a primarily motor donor nerve (femoral nerve branches) provides superior bladder reinnervation than a mixed sensory and motor nerve (GFN).25 We also found that the pudendal nerve could be reinnervated by transfer of motor branches of the femoral nerve.15, 47 We have not yet reinnervated the bladder, urethra and anal sphincters in the same animal that would be important to human patients to restore voiding function, fecal and urinary continence. The obturator nerve, like the femoral nerve, is a primarily motor nerve, and its natural path runs very close to the pelvic plexus. Animals will be decentralized by bilateral transections of L7 and all roots caudal to L7 in the spinal column. The obturator nerve will be transferred bilaterally to the anterior vesical branch of the pelvic nerve (OBNT-to-PN) and branches of the femoral nerve will be transferred bilaterally to the pudendal nerve (FNT-to-PudN) as it emerges from the pudendal (Alcock's) canal. Un-anesthetized urodynamics will be performed monthly for 6 months; half receiving implanted radiofrequency (RF) micro-stimulators for FES of transferred obturator and femoral nerve branches to monitor return of nerve stimulation evoked detrusor, urethra and anal sphincter pressures, before the terminal assays at 6 months. Aim 2 - To determine whether the bladder, urethra and anal sphincters remain capable of being reinnervated after prolonged decentralization for up to one year. We found in a group of 5 dogs that 4.5±0.9 months after decentralization, stimulation of sacral roots or spinal cord segments does not increase detrusor pressure, proving decentralization. However, stimulating anterior vesical branches of the pelvic nerve (between the pelvic plexus and bladder dome) increases detrusor pressure in 5 of 5 decentralized animals.25 We also proved that the bladder can be reinnervated by genitofemoral nerve transfer (GFNT) at 1 and 3 months after decentralization.46 The longer after decentralization that the bladder remains capable of being reinnervated, the more feasible this approach would be for human patients with long standing flaccid bladder paralysis. Bladders will be decentralized, as described for aim 1. Cuff electrodes interfaced with RF microstimulators will be placed on anterior vesical branches of the pelvic nerve and on pudendal nerve branches as they emerge from the pudendal canal in a subset of these animals. The effects of nerve stimulation on detrusor, urethral and anal sphincter pressure will be determined at monthly intervals starting 3-4 weeks after decentralization and continuing to 6 or 12 months. OBNT-to-PN and FNT-to-PudN will be performed in separate groups of animals at 6 and 12 months after decentralization. These groups will be compared to sham-decentralized animals with identically implanted RF micro-stimulators. This model will determine whether the distal pelvic plexus/ganglia-bladder, urethra and anal sphincter circuitry remain viable and capable of being reinnervated for periods of up to 1 year after decentralization to provide guidance for surgeons who would consider similar nerve transfer in the human following cauda equina injury. These proposed studies are designed to answer questions that will allow these surgical procedures to be widely accepted and applied to human patients with lower motor neuron lesioned bladder dysfunction; a group that includes patients with lower spinal cord injuries, spina bifida, pelvic or sacral fractures, and other neurological injuries to lower lumbar and sacral nerves.