钩藤碱抑制骶上脊髓损伤大鼠膀胱T型钙通道的机制

The mechanism of rhynchophyiline inhibiting T type calcium channel in bladder of suprasacral spinal cord injury rats

目的探讨钩藤碱对骶上脊髓损伤（SCI）大鼠的膀胱功能障碍治疗作用与膀胱逼尿肌T型钙通道受体亚型（alG）表达改变的关系。方法将60只SD大鼠随机分为钩藤碱组、对照组、假手术组，每组20只，造模后分别腹腔注射钩藤碱5mr／（kg·d）、等体积生理盐水、不给予药物干预。用尿动力仪评估膀胱功能；膀胱组织苏木素-伊红（HE）染色；用免疫组织化学法检测膀胱酪氨酸激酶受体（C—kit）、alG的表达。结果钩藤碱组膀胱最大容量较对照组增加（64．00±0．42）％、漏尿点压及收缩频率分别下降（16．004-0．31）％和（13．00±0．26）％（P〈0．01）。HE染色显示钩藤碱组逼尿肌紊乱及水肿程度较对照组低。免疫组织化学检测显示钩藤碱组大鼠C—kit、alG受体表达量较对照组明显下降。结论钩藤碱可抑制膀胱Cajal间质细胞（ICCs）表面ctlG的表达，从而降低骶上脊髓损伤后大鼠膀胱逼尿肌兴奋性。

Objective To investigate the relationship between the efficacy of rhynchophylline for bladder dysfunction in suprasacral spinal cord injury rats and T type calcium channel changes in bladder detusor. Methods Sixty female Spragne Dawley rats were randomly allocated into rhynchophylline group, control group, and sham operation group （n = 20 each）. After models established, rhynchophylline group was given intraperitoneal injection of rhynehophylline [ 5 ml/（ kg d） ] and control group given the same volume of saline, and sham group given no treatment. Urodynamics was monitored to evaluate the founction of bladder. Bladder tissue was stained with hematoxylin and eosin （HE） method. Immunohistochemical method was used to detect the expression level of al G and C - kit. Results The maximum bladder capaci- ty in rhynchophylline group was increased by （ 64. 00 ± 0. 42 ） % compared to control group, while the bladder leak point pressure and contraction frequency in rhynchophyllinc group were declined by （ 16.00 ± 0. 31 ） % and （ 13.00 ± 0. 26） %, respectively （ P 〈 0. 01 ）. HE staining showed detrusor disorder and mu- cosa edema in control group were more obvious than rhynchophylline group. The alG and C - kit expres- sion was significantly reduced in rhynchophylline group as compared with control group. Conclusion Rhynchophylline restrained the expression of T type calcium channel subtype al G on the surface of interstitial cells of Cajal （ICCs） in rat bladder, and then reduced the excitability of detrusor caused by suprasacral spinal cord injury.