人工膀胱反射弧的实验与临床研究

目的 建立人工膀胱反射弧,以恢复脊髓损伤后的膀胱功能,它将体反射运动是化的运动同支传入膀胱,引起膀胱的自主性收缩。方法 将犬右Ｌ５前根近端与右Ｓ２前根远端在硬膜内吻合,经轴突再生后,建立膝腱－脊髓中枢－膀胱人工反射通路。进行神经电生理、膀胱测压、膀胱逼尿肌 图等早期和无期功能观察。临床１例Ｔ２、３完全性截竣患者,硬膜内行双侧Ｌ５与Ｓ２前根的吻合。结果 单相方波（１１５ｍＶ,１．０ｍｓ）刺激右Ｌ５后     

Bypassing spinal cord injury: surgical reconstruction of afferent and efferent pathways to the urinary bladder after conus medullaris injury in a rat model

Afferent and efferent nerve function in the atonic bladder caused by conus medullaris injury in a rat model was established by intradural microanastomosis of the left L5 ventral root (VR) to right S2 VR to restore pure motor-to-motor reinnervation coupled with extradural postganglionic spinal nerve transfer of L5 dorsal root (DR) to S2 DR for pure sensory-to-sensory reinnervation. Early function of the reflex arc was evaluated by electrophysiological study, as well as by intravesicular pressure measurement and histological examination. The results demonstrated that single focal stimulation of the left S2 DR elicited evoked potentials at the left vesicular plexus before and after horizontal spinal cord damage between the L6 and S4 level. Bladder contraction was successfully initiated by trains of stimuli targeting the left L5-S2 DR anastomosis. Achievable bladder pressures and amplitude of bladder smooth muscle complex action potentials were unchanged before and after induced paraplegia and comparable to those of the control. Prominent axonal sprouting was seen in the distal part of nerve graft. Both afferent and efferent nerve pathways in the atonic bladder can be reconstructed by suprasacral motor-to-motor and sensory-to-sensory nerve transfer after spinal cord injury in rats. This reconstructive strategy has significant potential in clinical application.     

利用腹壁反射重建膀胱反射弧的远期功能性研究

目的：利用截瘫平面以上的腹壁反射通路建立SD大鼠的人工膀胱反射弧,以恢复脊髓损伤（SCI）后可控制性膀胱排尿功能。它包含了一个皮肤反射弧（下腹壁反射弧）,并将皮肤反射的运动冲动传入膀胱,引起膀胱的自主性收缩。方法：将SD大鼠右侧T13前根近端与右侧S2前根远端通过一段自体移植神经在硬膜囊内行显微缝合,保持T13后根完整,经一段时间轴突再生后,建立“腹壁反射－脊髓中枢－膀胱”这一新的人工膀胱反射弧。通过刺激右侧下腹壁反射激发截瘫动物排尿。神经缝合术后8个月,在破坏L5－S4脊髓节段前后,分别进行神经电生理、膀胱测压和神经药理学实验等远期功能观察。结果：在破坏L5－S4脊髓节段造成截瘫前后,单相方波（3mA,0.3ms）刺激实验测T13后根,12只SD大鼠的实验侧膀胱神经丛可记录到动作电位,其形态和波幅与对照组相似;串刺激（3mA,20Hz,5s）实验侧T13后根,经新建的膀胱人工反射弧引出膀胱平均内压达对照侧的76％,膀胱平滑肌复合肌肉运作电位平均最大波幅达对照侧81％,波形与对照组相似。在膀胱平滑肌内注射阿托品（0．05mg/kg）或三甲噻酚（5mg/kg）可抑制通过该人工反射弧激发的膀胱平滑肌收缩功能,而膀胱平滑肌肉注射维库溴铵（4mg/kg）对膀胱平滑肌收缩功能无影响。结论：体神经的运动传出支经自体神经移植,其轴突能够再生长入自主神经的副交感神经纤维,并具有良好的传导运动兴奋的功能,新的神经传导通路含有N1和M型受体,冲动传递的神经递质为乙酰胆碱;利用截瘫平面以上的体反射,通过硬膜囊内神经根自体神经移植缝合的方法,可建立新的人工膀胱反射弧,实现截瘫患者可控制性排尿。     

具有感觉传入通路的膀胱反射弧治疗脊髓损伤后弛缓性膀胱的实验研究

 目的 用SD大鼠构建具有感觉传入通路的膀胱反射弧,探讨其用于治疗脊髓损伤后弛缓性膀胱的有效性。方法 SD雄性大鼠24只,右侧为实验侧,先行L5前根近断端与S2前根远断端吻合,再将L5脊神经节周围突支近断端与S2后根远断端行端端吻合。左侧不做处理,为对照侧。术后3个月,破坏L6~S4节段脊髓造成弛缓性膀胱,于建模前后通过一般观察、神经电生理检测、神经示踪等方法观察反射弧构建情况。结果 21只大鼠存活至术后3个月,7只成功分离出吻合的脊神经。电刺激实验侧S2后根吻合口远端,均能检测到膀胱神经丛复合动作电位、膀胱平滑肌复合肌肉动作电位,截瘫前后动作电位差异无统计学意义;电刺激对照侧S2后根,在截瘫后未能检测到动作电位。实验侧膀胱神经丛复合动作电位和膀胱平滑肌复合肌肉动作电位平均波幅为截瘫前对照侧的71.9%和82.4%。神经示踪结果显示实验侧L5脊髓前、后角均可见青蓝色阳性反应颗粒。结论 构建具有感觉传入通路的膀胱反射弧,可使其运动、感觉神经通过轴突再生长入副交感神经纤维,并与脊髓前、后角重建轴突联系,轴浆运输功能得到重建,可用于弛缓性膀胱的治疗。     

体神经-内脏神经反射弧建立后脊髓损伤鼠排尿功能的改变以及可能机制

目的 建立新的体神经-内脏神经反射弧,应用尿流动力学方法来检测新反射弧建立后对清醒脊髓损伤(SCI)鼠膀胱功能及逼尿肌-尿道外括约肌协调性的影响以及可能机理。方法成年雄性大鼠(280～300)g在L4～L6的椎管内行L6腹侧根与L4腹侧根神经端端吻合,保留L4背根来传导来自新反射弧的皮肤传入信号。术后3个月行T9～T10椎间脊髓横断,8周后在清醒状态下检测容量诱发性排尿和电刺激新反射弧皮肤感觉传入区诱发排尿的膀胱压力变化图(CMG)和尿道外括约肌肌电图(EUS-EMG)各项参数的变化。结果 新的体神经-内脏神经反射弧建立后,在清醒状态下电刺激L4皮区可以诱发排尿,和不用电刺激的容量诱发性排尿(VEMR)相比排尿量增加、排尿压提高、排尿开放压提高,而残余尿减少,排尿效率明显增加,差异均有显著性(P<0.05)。EUS的肌电频率明显降低。结论 新反射弧建立后使 SCI鼠的排尿功能发生显著改变。电刺激反射弧的皮肤感觉区可以收缩膀胱逼尿肌使膀胱内压升高并同时使尿道外括约肌肌电频率下降,CMG和EUS的多项参数均有改善。逼尿肌-外括约肌不协调得到改善。     

脊髓损伤后膀胱人工反射弧建立的实验研究

目的 通过建立家犬人工膀胱反射孤,以恢复脊髓损伤后的膀胱功能。它包含一个体反射孤,并将体反射运动冲动经异化的运动传出支传入膀胱,引起膀胱的自主性收缩．方法 将右Ｌ５前根近端与右Ｓ２前根远端在硬膜囊内行显微吻合,保持Ｌ５后根完整,经轴突再生后,建立膝腱－脊髓中枢－膀胱这一新人工反射通路,通过刺激右侧膝腱激发排尿。神经根吻合术后６个月和１８个月,分别进行神经电生理、膀胱测压、膀胱逼尿肌肌电图等早期和远     

Micturition reflex arc reconstruction including sensory and motor nerves after spinal cord injury: Urodynamic and electrophysiological responses

Abstract

Objective

To evaluate artificial reflex arcs for micturition using urodynamics and electrophysiological recordings.

Design

Sixteen beagles were equally and randomly divided into two groups.

Methods

In group A, anastomosis of the proximal end of the left L7 ventral root (VR) and distal end of the left S2 VR was performed, as well as anastomosis of the L7 dorsal root (DR) and S2 DR to reconstruct the sensory and the motor function of the bladder. In group B the proximal end of the left L7 VR and the distal end of the left S2 VR were anastomosed, while the left L7 DR was kept intact to reconstruct the motor function of the bladder. Outcome measures included electrophysiological testing and the urodynamic measures. In addition, we also monitored urinary infection rates.

Results

Stimulation to the left S2 DR in groups A and B both elevated the bladder pressure before and after the spinal lower motor neuron lesion. Single stimulation of the two groups both elicited evoked action potentials. Urinary infections occurred in group A (three occurrences) and in group B (eight occurrences) during the 3 months after the spinal lower motor neuron lesion.

Conclusion

Data showed that both reconstructive methods could induce bladder micturition and evoked action potentials. However, in group A the micturition response was better and the urinary infection rates were lower after the spinal lower motor neuron lesion. Thus, the artificial physiological reflex arc reconstruction method used in group A, with sensory input above the lesion, might provide a better alternative in clinical practice.     

Long-term administration of prazosin improves bladder storage function: results from a study in spontaneously hypertensive rats

Objectives: To investigate the effects of long‐term administration of the α₁‐adrenoceptor antagonist prazosin on afferent inputs from the lower urinary tract (LUT). Methods: Twenty female spontaneously hypertensive rats (SHR) were randomized to receive a 4‐week course of prazosin (0.12 mg/kg per day) or vehicle; 10 female Wistar‐Kyoto (WKY) rats were given vehicle. Prazosin or vehicle was administered via an osmotic pump. The effect of prazosin on urodynamic parameters was determined by continuous cystometry in conscious animals. After cystometry, rats were killed and c‐fos expression in the dorsal horn of the L6 spinal cord was measured by immunohistochemistry. Results: The bladder contraction interval was significantly shorter in untreated SHR compared with WKY rats (2.36 ± 0 vs 4.27 ± 0.12 min, respectively; P < 0.05) and cystometric capacity was decreased significantly in SHR compared with WKY rats. L6 spinal cord c‐Fos expression was also significantly greater in SHR than WKY rats. The administration of prazosin significantly increased the micturition interval (4.07 ± 0.58 min; P < 0.05) and bladder capacity, but it did not affect micturition pressure. In SHR, the number of c‐Fos‐positive neurons was significantly lower following the administration of prazosin compared with vehicle. Conclusions: Increased afferent input from the LUT may induce an increase in urinary frequency in SHR. Furthermore, long‐term administration of prazosin can exert inhibitory effects on afferent pathways from the LUT during the storage phase. Reductions of afferent input can result in increased bladder capacity and increased micturition interval.     

Immunoneutralization of nerve growth factor in lumbosacral spinal cord reduces bladder hyperreflexia in spinal cord injured rats

PURPOSE: We investigated the effects of intrathecal application of nerve growth factor (NGF) antibodies (Ab) on bladder hyperreflexia in chronic spinalized rats. MATERIALS AND METHODS: In adult female rats an intrathecal catheter was implanted at the level of the L6 to S1 spinal cord, followed by complete transection of the Th8 to 9 spinal cord. At 10 days after spinalization the intrathecal catheter was connected to an osmotic pump for continuous delivery of vehicle or NGF Ab (10 microg daily) for 2 weeks. Awake cystometry was then performed. NGF levels in the L5 to S1 dorsal root ganglia, L6 spinal cord and bladder were also measured using enzyme-linked immunosorbent assay. RESULTS: The number of uninhibited bladder contractions per voiding cycle, maximal pressure of uninhibited bladder contraction and maximal voiding pressure were significantly decreased in NGF Ab treated versus vehicle treated spinalized rats. Intercontraction interval, baseline intravesical pressure, pressure threshold for voiding and voiding efficiency were not significantly changed by NGF Ab treatment. NGF levels in the bladder, L6 spinal cord and L5 to S1 dorsal root ganglia of vehicle treated spinalized rats was 1.6 to 4.8 times higher than in spinal cord intact rats. After intrathecal NGF Ab treatment NGF levels were significantly lower in the L6 to S1 dorsal root ganglia (30% to 35%) and L6 spinal cord (53%) but not in the bladder or L5 dorsal root ganglia compared with levels in vehicle treated spinalized rats. CONCLUSIONS: Increased levels of NGF in the bladder, spinal cord and dorsal root ganglia were associated with bladder hyperreflexia after spinal cord injury. Immuno-neutralization of NGF in the spinal cord suppressed NGF levels in the L6 to S1 dorsal root ganglia, which contain bladder afferent neurons, and also suppressed bladder hyperreflexia. Thus, suppression of NGF levels in afferent pathways could be useful for treating bladder hyperreflexia associated with spinal cord injury.     

建立人工膀胱反射弧治疗脊髓损伤后弛缓性膀胱的实验研究

目的探讨利用脊髓损伤平面以上健存的体反射重建人工膀胱反射弧,恢复脊髓损伤(spinalcordinjury,SCI)后膀胱排尿功能。方法1岁龄雄性Beegle犬8只,体重9.5±2.0kg。取后正中切口暴露L4～S3的棘突和椎板,全椎板切除后暴露硬膜和脊神经根,在硬膜外初步分离和确认L6和S2前根。确定犬左侧为实验侧,将左侧L6与S2前根分别在穿神经根管处切断,切开硬膜囊,从硬膜外L6和S2前根追溯硬膜内神经根,在显微镜下将L6和S2前根在硬膜内吻合。经一段时间轴突再生后,建立“膝腱-脊髓中枢-膀胱”人工反射弧。神经缝合术后8个月,在破坏S1～S4脊髓节段前后,分别进行神经电生理、膀胱肌电图及尿流动力学等远期功能观察。结果术后8个月,3只犬死亡,3只犬未能分离出吻合的神经,无实验结果。余2只犬均获得满意结果,定为1号和2号犬,进行观察。刺激(连续刺激强度200μV,刺激间隔为5ms)截瘫前和截瘫后2只犬左侧L6后根、神经吻合口,均可在吻合口远端记录到运动诱发电位,其波形和波幅相似;尿流动力学检查可见,当刺激开始时膀胱内压迅速上升,而腹内压增加幅度较小,刺激中止后膀胱内压迅速下降,证实膀胱内压升高主要是由逼尿肌收缩产生,电刺激左侧L6后根和吻合口膀胱内压升高值均可达到正常的60%左右。结论利用脊髓损伤平面以上健存的体反射重建膀胱反射通路是成功和有效的,体神经的运动支通过轴突再生能够长入自主神经的副交感神经纤维,并具有良好的传导运动兴奋的功能。     

Dynamic Bulbocavernosus Reflex: Dyssynergia Evaluation Following SCI

ABSTRACT

High urethral resistance caused by detrusor-sphincter dyssynergia (DSD) occurs following spinal cord injury (SCI) and results in poor voiding. A major pelvic floor reflex that may be involved in DSD is the bulbocavernosus reflex (BC) and evaluation of this reflex during the micturition cycle may provide additional information regarding this role. The periodic BC observed during micturition via cystometry is described as a dynamic bulbocavernosus reflex (DBC).

The DBC was induced in upper motor neuron SCI patients using periodic dorsal penile nerve stimulation; the evoked reflex response was recorded with an anal sphincter pressure sensing balloon. Stimulation of 15–50 mA was applied at the base and dorsal side of the penis with surface electrodes, pulsed at a rate of 0.25 Hz. By applying the stimulation during cystometry, the BC reflex could be evaluated throughout the entire micturition cycle. Results showed that the DBC increased during bladder filling and bladder contractions. These findings indicate that an enhanced BC reflex is a major factor causing increased urethral resistance during micturition. (J Am Paraplegia Soc: 17; 140–145)     

大鼠骶神经根对膀胱功能选择性支配的实验研究

目的：研究骶神经根对膀胱功能的选择性支配，为临床脊髓损伤(SCI）后的膀胱功能重建及建立实验性人工膀胱动物模型提供依据。方法：对10只SCI的SD大鼠进行硬膜外S1～S4骶神经根电刺激，记录膀胱神经丛动作电位和膀胱平滑肌复合肌肉动作电位变化，同时通过膀胱内插入测压管并经压力换能器记录膀胱内压的变化。结果：SD大鼠的S1～S4骶神经均参与膀胱神经功能支配，其中以S2骶神经最主要，S1、S3骶神经次之，S4骶神经的支配作用最小。结论：不同的骶神经根对膀胱平滑肌的支配效能不同，利用膀胱平滑肌的主要支配神经根进行人工电刺激排尿或通过神经吻合重建人工膀胱反射弧，对提高SCI后的膀胱排尿功能有一定的临床意义。     

Neural control of the urinary bladder: Possible relationship between peptidergic inhibitory mechanisms and detrusor instability

This paper provides a brief review of the organization of the neural mechanisms controlling micturition. The role of neuropeptides in peripheral afferent and efferent pathways and in the central reflex mechanisms is discussed. A major focus of the paper is on the inhibitory functions of spinal and supraspinal enkephalinergic systems in the control of bladder capacity and bladder stability. Pharmacological studies indicate that drug-induced changes in enkephalinergic mechanisms can elicit marked alterations in bladder function. Similar changes in transmitter mechanisms may occur following neural injury or disease and therefore be involved in the development of neurogenic disorders of the lower urinary tract.     

Voiding reflex in chronic spinal cord injured cats induced by stimulating and blocking pudendal nerves

AIMS: To induce efficient voiding in chronic spinal cord injured (SCI) cats. METHODS: Voiding reflexes induced by bladder distension or by electrical stimulation and block of pudendal nerves were investigated in chronic SCI cats under alpha-chloralose anesthesia. RESULTS: The voiding efficiency in chronic SCI cats induced by bladder distension was very poor compared to that in spinal intact cats (7.3 +/- 0.9% vs. 93.6 +/- 2.0%, P < 0.05). In chronic SCI cats continuous stimulation of the pudendal nerve on one side at 20 Hz induced large amplitude bladder contractions, but failed to induce voiding. However, continuous pudendal nerve stimulation (20 Hz) combined with high-frequency (10 kHz) distal blockade of the ipsilateral pudendal nerve elicited efficient (73.2 +/- 10.7%) voiding. Blocking the pudendal nerves bilaterally produced voiding efficiency (82.5 +/- 4.8%) comparable to the efficiency during voidings induced by bladder distension in spinal intact cats, indicating that the external urethral sphincter (EUS) contraction was caused not only by direct activation of the pudendal efferent fibers, but also by spinal reflex activation of the EUS through the contralateral pudendal nerve. The maximal bladder pressure and average flow rate induced by stimulation and bilateral pudendal nerve block in chronic SCI cats were also comparable to those in spinal intact cats. CONCLUSIONS: This study shows that after the spinal cord is chronically isolated from the pontine micturition center, bladder distension evokes a transient, inefficient voiding reflex, whereas stimulation of somatic afferent fibers evokes a strong, long duration, spinal bladder reflex that elicits efficient voiding when combined with blockade of somatic efferent fibers in the pudendal nerves.     

Autonomic neuropathy in BB rats and alterations in bladder function

In vivo urinary bladder function was examined in BB rats after 4 and 6 mo of diabetes, and the data were correlated with morphometric changes in the pelvic and hypogastric nerves, which constitute the micturition reflex arc. After controlled bladder distension, diabetic animals revealed irregular bladder contractions at frequencies that were reduced to 33% of normal values and with significantly increased amplitudes. The abnormal micturition in diabetic animals was elicited at moderately elevated threshold volumes. These functional abnormalities of the diabetic bladder were associated with a progressive axonopathy of afferent myelinated sensory fibers and later-occurring axonal atrophy of unmyelinated efferent preganglionic fibers. These data suggest that diabetic urinary bladder dysfunction is initiated by a visceral sensory neuropathy involving the afferent limb of the micturition reflex arc.     

人工膀胱反射弧的远期功能观察

目的 :建立犬人工膀胱反射通路 ,以恢复脊髓损伤后的膀胱功能 ,观察人工反射弧的远期功能状态。方法 :将右L5前根近端与右S2 前根远端在硬膜囊内吻合 ,经轴突再生后 ,建立膝腱—脊髓中枢—膀胱这一新的人工膀胱反射通路 ,通过刺激膝腱激发排尿。结果 :神经根吻合术后 18个月 ,T10 平面截瘫 48h后 ,通过电刺激传入神经 ,经新建的反射弧引出的膀胱收缩平均可达正常的 84% ,敲击膝腱引出的膀胱收缩平均达正常的 6 2 % ;电刺激右L5后根和右股神经 ,均可记录到膀胱逼尿肌肌电图 ,其形态和波幅与对照组相似。结论 :体神经的运动传出支通过轴突再生能够长入自主神经的副交感性纤维 ,并具有良好的传导运动兴奋的功能 ;利用截瘫平面以下健存的体反射 ,通过神经根吻合的方法 ,可建立人工膀胱反射弧 ,实现患者的控制性排尿。     

Reconstructed Bladder Innervation Below the Level of Spinal Cord Injury: The Knee-Tendon to Bladder Artificial Reflex Arc

Background/Objective: To study the effectiveness of knee-tendon to bladder artificial reflex arc in dogs.

Methods: In 6 beagles, the proximal end of the right L5 anterior motor root and the distal end of the right S2 anterior root were anastomosed to build a knee-tendon to bladder reflex, whereas the right L5 posterior sensory root was kept intact. Action potential (AP) curves and electromyograms (EMGs) of the detrusor muscle, the intravesical pressure, horseradish peroxidase (HRP)-labeled neurons, and the passing rates of myelinic nerve fibers were calculated to evaluate its feasibility.

Results: AP curves and EMG detected in all 6 dogs were similar to those of the control. Six and 18 months after surgery, the means for bladder contraction induced by percussion of the right knee-tendon were 38 ± 27% and 62 ± 5% that of the normal control, respectively. The mean duration times induced by percussion of the right knee-tendon at 6 and 18 months after surgery were 51 ± 37% and 84 ± 12% that of the normal control, respectively. HRP retrograde tracing and neurohistologic observation indicated the feasibility of the artificial reflex arc.

Conclusions: Our data showed the effectiveness of bladder innervation below the level of spinal cord injury producing urination by knee-tendon to bladder reflex contractions, and therefore, might provide a new clinical approach for restoring bladder function in individuals with paraplegia.     

Efferent and afferent neuronal hypertrophy associated with micturition pathways in spontaneously hypertensive rats

Elevated nerve growth factor secreted by bladder smooth muscle may be associated with noradrenergic hyperinnervation of the bladder and hyperactive voiding in spontaneously hypertensive rats (SHR) and rats with bladder outlet obstruction. The present study was undertaken to determine if changes occur in efferent and afferent pathways supplying the SHR bladder similar to those in rats with bladder outlet obstruction. Fluoro-Gold (FG) retrograde tracing studies were conducted to examine the postganglionic efferent limb (major pelvic ganglion; MPG) and sensory afferent limb (L₁, L₂, L₆, and S₁ dorsal root ganglion; DRG) of the micturition reflex pathway of the SHR and Wistar-Kyoto (WKY) normotensive rat. A significant increase in cross sectional area profiles for labeled neurons in the MPG was observed in SHRs (830.5 ± 9.0 μm²) as compared to WKYs (736.3 ± 16.6 μm²). Neuronal cell areas in L₂ (1,010.9 ± 18.6 μm²) and S₁ (1,024.6 ± 28.3 μm²) of SHRs were significantly larger than those of WKYs (L2, 865.3 ± 12.6 μm²; S1, 778.3 ± 11.2 μm²). There was an increase in number of labeled cells in L₆ within SHRs over WKYs. These results provide evidence that both efferent and afferent changes in neuronal innervation of the bladder occur in SHRs. The SHR strain may represent a genetic model to study changes in micturition reflex pathways that result from alterations in neuronal morphology such as those that occur with urethral outlet obstruction. Neurourol. Urodynam. 16:293–303, 1997. © 1997 Wiley-Liss, Inc.     

Bladder inhibition or excitation by electrical perianal stimulation in a cat model of chronic spinal cord injury

OBJECTIVE

To test the hypothesis that perianal electrical stimulation (PES) in chronic spinal cord‐injured (SCI) cats could induce frequency‐dependent inhibitory or excitatory reflex bladder responses.

MATERIALS AND METHODS

The experiments were conducted ≥4–5 weeks after spinal cord transection at the T9‐T10 level. PES was applied via a pair of hook electrodes to the perianal skin area in three awake female cats with chronic SCI. A double‐lumen balloon catheter was inserted through the urethra into the bladder to monitor bladder pressure and infuse saline (2–4 mL/min).

RESULTS

Under isovolumetric conditions PES at 3–10 Hz significantly inhibited large‐amplitude reflex bladder activity induced by bladder distension above the micturition volume threshold. However, PES at 20–50 Hz induced large‐amplitude bladder contractions when the bladder volume was below the micturition volume threshold. Inhibitory PES (7 Hz) significantly increased the mean (sem ) bladder capacity by 40 (10)% when it was applied continuously during cystometrography. The optimum excitatory PES (30 Hz) induced large‐amplitude (>25 cmH₂O), long‐duration (>20 s) bladder contractions at a wide range of bladder volumes (10–90% of bladder capacity).

CONCLUSIONS

This study showed that activation of pudendal afferent fibres by PES could induce frequency‐dependent reflex bladder responses in awake cats with chronic SCI, indicating that a possible noninvasive treatment based on PES could be developed to restore both continence and micturition function for patients with SCI.     

人工反射弧重建膀胱功能动物模型的建立

目的 :建立犬“膝腱 脊髓 膀胱”反射弧重建膀胱功能的动物模型 ,作为实验研究人工膀胱反射弧的基础。方法 :家犬 5条 ,行硬膜外L5 S2前根交叉吻接 ,饲养 1年后刺激反射弧并记录膀胱压和尿道压变化。结果 :5只家犬“膝腱 脊髓 膀胱”反射弧均成功建立 ,刺激反射弧时膀胱压和尿道压都有升高。结论 :通过硬膜外L5 S2前根交叉吻接可以更有效地建立人工反射弧重建膀胱功能的动物实验模型。