CAJ | 학술논문

目的探讨大鼠神经源性尿路功能障碍(neurogenic urinary tract dysfunction,NUTD)输尿管平滑肌细胞(ureteral smooth muscle cells,USMC)超微结构改变及小电导钙激活钾通道(small conductance Ca2+-activated K+ channels,SKca)表达变化.方法选取45只SD大鼠随机平均分为NUTD组、实验对照组(EC组)和空白对照组(BC组).其中NUTD组给予破坏S1～4脊髓节段,术后1周行影像尿动力学检查,证实存在逼尿肌无收缩但无膀胱输尿管发生反流;EC组仅咬除棘突,未破坏脊髓;术后1周行影像尿动力学检查,证实无明显膀胱尿道功能障碍.模型建立后6周三组大鼠均行影像尿动力学检查,输尿管功能和形态学及USMC超微结构观察,并应用荧光定量PCR和Western-blot检测USMC SKca mRNA和蛋白表达情况.结果模型建立后6周NUTD组大鼠膀胱均表现为无逼尿肌过度活动、膀胱逼尿肌无收缩.30 min内NUTD组产生尿量为(0.90±0.17)ml,EC组为(0.86±0.18)ml,BC组为(0.94±0.15)ml三组间差异无统计学意义;但NUTD组输尿管蠕动频率(16.23±2.35)次/5 min显著低于EC组(21.80±1.97)次/5 min和BC组(20.47±2.48)次/5 min,差异有统计学意义(P＜0.05).NUTD组USMC中SKca2和SKca3蛋白表达显著上调,mRNA表达相对于BC组平均分别上调4.15和4.56倍,差异有统计学意义(P＜0.01).电镜下可见NUTD组USMC排列散乱,线粒体体积增大水肿、数量增多,线粒体嵴增粗、髓样变,部分细胞可见线粒体内膜和嵴膜的大量破坏.结论 USMC超微结构改变和SKca表达水平上调可能是输尿管原发性功能障碍的重要机制之一.
목적 탐토대서신경원성뇨로공능장애(neurogenic urinary tract dysfunction,NUTD)수뇨관평활기세포(ureteral smooth muscle cells,USMC)초미결구개변급소전도개격활갑통도(small conductance Ca2+-activated K+ channels,SKca)표체변화.방법 선취45지SD대서수궤평균분위NUTD조、실험대조조(EC조)화공백대조조(BC조).기중NUTD조급여파배S1～4척수절단,술후1주행영상뇨동역학검사,증실존재핍뇨기무수축단무방광수뇨관발생반류;EC조부교제극돌,미파배척수;술후1주행영상뇨동역학검사,증실무명현방광뇨도공능장애.모형건립후6주삼조대서균행영상뇨동역학검사,수뇨관공능화형태학급USMC초미결구관찰,병응용형광정량PCR화Western-blot검측USMC SKca mRNA화단백표체정황.결과 모형건립후6주NUTD조대서방광균표현위무핍뇨기과도활동、방광핍뇨기무수축.30 min내NUTD조산생뇨량위(0.90±0.17)ml,EC조위(0.86±0.18)ml,BC조위(0.94±0.15)ml삼조간차이무통계학의의;단NUTD조수뇨관연동빈솔(16.23±2.35)차/5 min현저저우EC조(21.80±1.97)차/5 min화BC조(20.47±2.48)차/5 min,차이유통계학의의(P＜0.05).NUTD조USMC중SKca2화SKca3단백표체현저상조,mRNA표체상대우BC조평균분별상조4.15화4.56배,차이유통계학의의(P＜0.01).전경하가견NUTD조USMC배렬산란,선립체체적증대수종、수량증다,선립체척증조、수양변,부분세포가견선립체내막화척막적대량파배.결론 USMC초미결구개변화SKca표체수평상조가능시수뇨관원발성공능장애적중요궤제지일.
Objective To explore the changes of ureteral ultrastructure in rats with neuropathic urinary tract dysfunction (NUTD) and the expression of small conductance Ca2+ activated K+ channels (SKca) in ureteral smooth muscle cell.Methods A total of 45 rats weighted 200 g were randomly divided into 3 groups of NUTD,experimental control (EC) and blank control (BC).The NUTD group underwent spinal cord transection at the first lumbar level and a destruction of sacral cord.EC group had a mere removal of spinous process at the same position,an exposure of spinal cord and there was no transection;BC group had no operation.One week later,video-urodynamics showed that there was indeed acontractile detrusor (ACD),no expanded bladder capacity and vesicoureteral reflux (VUR) in rats from NUTD group and no significant urinary tract dysfunction in rats from experimental control and blank control groups.Video-urodynamics,observation of ureteral ultrastructure and morphology were performed at Week 6 post-operation.The expressions of mRNA and protein of SKca in ureteral smooth muscle cell (USMC) were measured by real-time fluorescent quantitative polymerase chain reaction (PCR) and Western blot after 6 weeks.Meanwhile fine structures of ureteral smooth muscle cell were observed by electron microscopy.Results Acontractile detrusor (ACD) and expanded bladder capacity were found in all rats from NUTD group without vesicoureteral reflux.No significant difference existed in urine volume per 30 min among three groups (NUTD group:0.90 ± 0.17 ml,EC group:0.86 ± 0.18 ml,BC group:0.94 ± 0.15 ml).The 5-min peristaltic frequency of left ureter was significantly lower in NUTD group (16.65 ±-2.35) than those of EC group (21.80-± 1.97) and BC group(20.47-± 2.48,P＜0.05).No abnormal gross changes occurred in ureteral lamina epithelium,lamina propria and muscular layer among three groups.Compared with BC group,the mRNA expressions of SKca2 and SKca3 were up-regulated for 4.15 and 4.56 folds in NUTD group respectively (P＜0.01).And the protein expressions of SKca2 and SKca3 also significantly increased (P＜ 0.01).Under electron microscopy,the permutations of smooth muscle were scattered and there were plenty of expanded and edematous mitochondria with crest medullary enlargement;extensive damage of intima and ridge membrane.Conclusions A downregulation of SKca and altered ultrastructure in USMC may play an important role in primary upper urinary tract dysfunction.