腰椎间盘突出导致神经原性膀胱模型的建立及其尿动力学评价

Establishment of a new model of neurogenic bladder dysfunction caused by lumbar intervertebral disk hernia and its urodynamic evaluation

目的建立腰椎间盘突出导致神经原性膀胱的大鼠模型,并对模型进行尿动力学评价。方法将20只雄性 Wistar 大鼠随机分为两组,手术组15只,假手术组5只。将平头螺丝钉置入大鼠的 L_6-S_1节段椎间盘,建立大鼠腰椎间盘突出模型。术后进行电子 X 线摄片和联合行为评分(CBS),并在术后4周对所有大鼠行耻骨上膀胱造瘘,造瘘后3 d 进行大鼠清醒状态的膀胱测压检查。结果术后电子 X 线摄片证实螺丝钉置入 L_6-S_1节段椎间盘;观察时间内手术组 CBS 评分均显著高于假手术组(均 P<0.05),且在术后1周后,各组 CBS 评分基本保持不变;大鼠清醒状态的膀胱测压结果显示,与假手术组相比,手术组充盈期膀胱自发性收缩频率(t=4.425,P=0.000)、最大膀胱容量(t=5.141,P=0.002)较高,膀胱顺应性(t=2.891,P=0.011)较低,尿动力学检查证实大鼠腰椎间盘突出导致神经原性膀胱模型建立成功。结论应用螺丝钉置入椎间盘方法可获得可靠的大鼠腰椎间盘突出导致神经原性膀胱的模型,可通过电子 X 线摄片、CBS 评分和尿动力学检查等加以证实。

Objective To establish a new rat model of neurogenic bladder dysfunction caused by lumbar intervertebral disk hernia, and to confirm the model by urodynamic examination. Methods Twenty male Wistar rats were divided into two groups at random： experimental group （n = 15 ）and pseudo-operation group （ n = 5 ）. The rats underwent laparotomy to disclose the intervertebral disk of L6-S1 , and a 1.50 mm × 4.50 mm blunt screw with flat end was inserted into the intervertebral disk of L6-S1 of the rats in the experimental group so as to establish the model of lumbar intervertebral disk hernia. Computed radiography （CR） was performed 3 days after the operation to conform the successful insertion of the screw. Combined behavioral score （CBS） was used 1 d, 3 d, 1 week, 2 weeks, and 4 weeks after the operation. Four weeks after the laparotomy a vesical fistula above the pubis was made in all of the rats, and then urodynamic examination was performed three days after this operation. Results CR after operation confirmed that the blunt screw had been inserted into the lumbar disk of L6. The CBS scores of the 2 groups at different time points all decreased along with time, and basically remained unchanged lweek after. The CBS scores of the experiment group were significantly higher than those of the pseudo-operation group （ all P 〈 0.05 ）. The spontaneous vesical contraction rate in the filling period of the experimental group was （4.37 ± 2.13 ） times/ rain, significantly higher than that of the pseudo-operation group [ （0.06 ± 0.13 ） times/min, t = 4. 425, P = O. 000 ], the maximum bladder capacity of the experimental group was （ 1.20± 0.34 ） ml, significantly greater than that of the pseudo-operation group [ （0.60 ± 0.14） ml, t = 5. 141, P = 0. 002 ] , and bladder compliance of the experimental group was （0. 024 ± 0.012 ） ml/cm H20 , significantly lower than that of the pseudo-operation group [ （0. 096 ± 0. 088 ） ml/cm H2O,t = 2. 891, P = 0. 011 ], and the leak point pressure of the experimental group was （ 75 ± 27 ） cm H2O, not significantly different from that of the pseudo-operation group [ （62 ± 23 ） cm H20 ]. The urodynamic examination on the conscious rats confirmed the successful establishment of the neurogenic bladder dysfunction caused by lumbar intervertebral disk hernia. Conclusion A new model of neurogenic bladder dysfunction caused by lumbar intervertebral disk hernia has been established by insertion of a blunt screw into the lumbar intervertebral disk of L6. The model is confirmed by urodynamic examination.