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来重新神经支配下运动神经元损伤的膀胱、尿道和肛门括约肌。我们已经非常成功地使用犬模型来证明躯体神经可以改道到骨盆神经的膀胱前分支（在骨盆丛和膀胱圆顶之间）以再神经支配膀胱肌肉。我们发现，电刺激这些转移的神经可以增加逼尿肌压力并诱导膀胱排空，并使用逆行追踪方法证实了这些改道神经的再生。在这些外科手术被广泛接受并应用于患有下运动神经元损伤的人类患者之前，我们需要在这种动物模型中回答一些临床相关的问题。膀胱功能障碍临床上最相关的问题是，这种神经再支配是否真的改善了清醒动物的储存和排空功能？ 这将在以下目标中通过使用植入的 射频（RF）微刺激器和功能性电刺激（FES）的改道神经，25，45，46在非麻醉动物定期作为他们的膀胱和尿道括约肌成为再神经支配在6个月的术后观察期。在安乐死时，将使用电生理学、药理学、神经解剖学和神经生物学方法探索对神经再支配的影响。 目的1 -确定闭孔神经移位是否能重建膀胱神经， 通过股神经分支的转移对尿道和肛门括约肌进行神经再支配提供了排尿和排空功能的恢复。我们发现移植主要是运动神经的供体神经（股神经分支）提供了比感觉和运动神经混合（GFN）更好的上级膀胱神经再支配。25我们还发现，阴部神经可以通过股神经运动分支的转移来再支配。15，47我们还没有对膀胱进行神经再支配，尿道和肛门括约肌在相同的动物，这将是重要的人类患者恢复排尿功能，粪便和尿液排泄。闭孔神经，像股神经一样，是一种主要的运动神经，其自然路径非常长。 靠近盆腔神经丛通过双侧横断L7和脊柱中L7尾侧的所有神经根将动物分散。闭孔神经将转移到双侧 骨盆神经的前膀胱分支（OBNT-至-PN）和股神经的分支将在阴部神经（FNT-至-PudN）从阴部（Alcock）管出现时双侧转移至阴部神经。将每月进行一次非麻醉尿动力学检查，持续6个月;在6个月的终末试验前，一半接受植入的射频（RF）微刺激器，用于转移的闭孔神经和股神经分支的FES，以监测神经刺激诱发的逼尿肌、尿道和肛门括约肌压力的恢复。 目的2 -确定膀胱、尿道和肛门括约肌是否仍然能够被 经过长达一年的长期权力下放，我们在一组5只狗中发现，在去中心化后4.5±0.9个月，刺激骶神经根或脊髓节段不会增加逼尿肌压力，证明了去中心化。然而，刺激骨盆神经的膀胱前支（盆丛和膀胱顶之间）增加了5只分散动物中的5只的逼尿肌压力。25我们还证明了膀胱可以在分散后1个月和3个月通过生殖股神经转移（GFNT）进行再神经支配。46分散后膀胱保持能够再神经支配的时间越长，这种方法对于长期存在的弛缓性膀胱麻痹的人类患者就越可行。如目标1所述，囊袋将下放。将与RF微刺激器连接的袖带电极放置在骨盆神经的前膀胱分支和阴部神经分支上，因为它们从这些动物的一个子集的阴部管中出现。从分散后3-4周开始，每月测定一次神经刺激对逼尿肌、尿道和肛门括约肌压力的影响，并持续至6或12个月。在分散后6个月和12个月，将在不同的动物组中进行OBNT至PN和FNT至PudN。将这些组与植入相同RF微刺激器的假分散动物进行比较。该模型将确定远端盆腔神经丛/神经节-膀胱、尿道和肛门括约肌回路是否仍然可行，并且能够在分散后长达1年的时间内重新神经支配，以为外科医生提供指导，这些外科医生将考虑在人类马尾损伤后进行类似的神经转移。 这些拟议的研究旨在回答一些问题，这些问题将使这些外科手术被广泛接受并应用于患有下运动神经元损伤膀胱功能障碍的人类患者;一组包括患有下脊髓损伤、脊柱损伤和脊髓损伤的患者。 裂、骨盆或骶骨骨折以及对下腰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.