骶神经对下尿路的支配及功能影响的实验研究

目的：了解S2？S4神经根对膀胱、尿道及阴茎主要支配分布及功能影响，为高选择性神经根切断治疗脊髓损伤后痉挛性膀胱提供实验依据。方法：分别电刺激家犬S2？S4神经根，观察记录逼尿肌、括约肌收缩状况，膀胱压力变化及阴茎勃起状态，并对其运动诱发电位峰值进行比较分析。结果：电刺激S2神经根引起的逼尿肌运动诱发电位峰值及膀胱压力变化可达到正常的60％，电刺激S3神经根引起的括约肌运动诱发电位峰值可达正常的57％，电刺激S4神经根可使犬阴茎勃起程度较高。结论：S2？S4神经分别为膀胱逼尿肌、尿道括约肌及阴茎的主要支配神经。此对于进一步重建和恢复截瘫后下尿路功能且避免在治疗过程中引起不必要的功能损害，奠定了必要的实验基础。

Experimental study of sacral nerve distribution and its influence on lower urina ry tract function

Objective: To study the main distribution and the influence of S2S4 nerves on urethral sphincter, detrusor urinae and penis. To supply the theoretical guidance for the treatment of spastic bladder after spinal cord injury with differential sacral rhizotomy. Methods: Twelve dogs were respectively given electrical stimulation to S2S4 nerve roots. The contraction of urethral sphincter and detrusor urinae, the change of bladder pressure and penis erection were examined and recorded. The peak value of evoked motor unit potentials of the corresponding muscles were compared. Results: Electrical stimulation to S2 nerve root induced peak value of evoked motor unit potential of detrusor urinae and change of bladder pressure which amounted to 60% of that under normal condition. Electrical stimulation to S3 nerve root induced peak value of evoked motor unit potential of musculus sphincter urethrae which amounted to 57% of that under normal condition. Electrical stimulation to S4 nerve root induced improved penis erection. Conclusion: S2S4 nerves are the main innervating nerves to detrusor urinae, urethral sphincter and penis respectively. This finding helps to further rehablitate and recover the function of the lower urinary tract after spinal cord injury and avoid unnessesary functional damage in the course of treatment.