转化生长因子、碱性成纤维细胞生长因子与大鼠膀胱出口梗阻后逼尿肌收缩功能障碍的关系

Relationship of transforming growth factor β1 and basic fibroblast growth factor to detrusor underactivity following bladder outlet obstruction： experiment with rats

目的探讨转化生长因子β1（TGFβ1）、碱性成纤维细胞生长因子（bFGF）与大鼠膀胱出口梗阻（BOO）后逼尿肌收缩功能障碍的关系。方法建立Wistar大鼠BOO模型（BOO2周组11只；BOO6周组10只），假手术组（8只）作为对照，测定离体逼尿肌肌条M受体激动剂刺激下收缩力，RT-PCR方法测定逼尿肌中TGFβ1 mRNA、bFGF mRNA的表达，ELISA测定尿液中TGFβ1、bFGF的水平。结果在1×10^-4、1×10^-3mmol／L氯化氨基甲酰胆碱（Carbachol）浓度下BOO2周组的最大逼尿肌收缩力[（0．96±0．11）、（1．98±0．21）g]大于对照组[（0．85±0．18）、（1．82±0．19）g，均P〈0．05]；大鼠在1×10^-5、1×10^-4、1×10^-3和1×10^-2mmol／LCarbachol浓度下BOO6周组的最大逼尿肌收缩力[（0．19±0．02）、（0．65±0．06）、（1．12±0．08）和（1．40±0．19）g]均小于BOO2周组[（0．24±0．03）、（0．96±0．11）、（1．98±0．21）和（2．16±0．21）g，均P〈0．05]和对照组[（0．23±0．04）、（0．85±0．18）、（1．82±0．19）和（2．12±0．26）g，均P〈0．05]。TGFβ1 mRNA在对照组、BOO2周组、BOO6周组逼尿肌的表达分别为0．32±0．01、0．34±0．10和0．72±0．21，后两组之间差异有统计学意义（P〈0．01）；bFGF mRNA表达分别为0．10±0．05、0．21±0．07和0．38±0．13，组间两两比较，差异均有统计学意义（均P〈0．05）。离体逼尿肌收缩力与其TGFβ mRNA、bFGF mRNA表达水平呈负相关（均P〈0．05）。BOO6周组尿中TGFβ1表达[（606±216）μg／mol肌酐]明显高于BOO2周组[（131±49）μg／mol肌酐]和对照组[（107±22）μg／mol肌酐，均P〈0．05]。结论逼尿肌bFGF mRNA表达随BOO进展持续升高，TGrβ1 mRNA在失代偿阶段表达才明显升高；尿液TGFβ1在大鼠BOO6周时呈强表达，有可能成为预测BOO后逼尿肌收缩功能的指标。

Objective To investigate the relationship of transforming growth factor 61 （TGFβ1） and basic fibroblast growth factor （bFGF） to detrusor underactivity following bladder outlet obstruction （BOO）. Methods Female Wistar rats underwent ligation of the urethra to establish BOO models and were divided into BOO model 2-week group （11 rats） and BOO model 6-week group （10 rats）. 8 rats underwent sham operation as control group. The detrusor urinae was taken out and stimulated by carbachol to measure the detrusor contraction force （DCF）. RT-PCR method was employed to measure the mRNA expression of TGFβ1 and bFGF in the detrusor urinae. Urine TGFβ1 and bFGF were determined by ELISA. Results The maximum DCF levels of the BOO 2-week group under the 1 × 10^-4 mmol/L and 1 × 10^-3 mmol/L carbachol concentrations were 0.96 g ±0.11 g and 1.98 g ± 0.21 g respectively, both significantly higher than those of the sham operation group （ 0.85 g ± 0. 18 g and 1.82 g ± 0.19 g respectively, both P 〈 0.05）. The maximum DCF levels of the BOO 6-week group under the 1 × 10^-3, 1 × 10^-4, 1 × 10^-3 and 1 × 10 ^-2 mmol/L carbachol concentrations were 0.19 g ± 0.02 g, 0.65 g ± 0.06 g, 1.12 g ± 0.08 g, and 1.40 g ± 0.19 g respectively, all significantly lower than those of the BOO 2-week group （0.24 g ± 0.03 g,0.96 g±0.11 g, 1.98 g±0.21 g, and 2.16 g±0.21 g respectively, all P〈0.05） and those of the sham operation group （0.23 g ± 0. 04 g, 0. 85 g ± 0. 18 g, 1.82 g ± 0.19 g, and 2.12 g ± 0.26 g respectively, all P 〈 0.05 ）. The mRNA expression of TGFβ1 of the BOO 6-week group, BOO 2-week group, and sham operation group was 0.72 ± 0.21, 0.34 ± 0. 10, and 0.32 ± 0.01 respectively, there was a significant difference between the BOO 6-week group and the BOO 2-week group （P 〈0.01 ）. The mRNA expression level of bFGF of the BOO 6-wwek group was O. 38 ± 0. 13, significantly higher than those of the BOO 2- week group and sham operation group （0.21 ± 0.07 and 0.10 ± 0.05 respectively, both P 〈0.05 ）. DCF was negatively correlated with the mNRA expression of TGFβ1 and the mNRA expression bFGF in detrusor （both P〈0.05）. The urine TGFβ1 of the BOO 6-week group was （606 ±216） μg/mol Cr, significantly higher than that of the BOO 2-week group [ （131 ± 49）μg/mol Cr] and that of the sham operation group [ （ 107 ± 22） μg/mol Cr, both P 〈 0.05 ]. Conclusion With the progression of BOO, there is a sustained rise of bFGF mRNA expression in detrusor; however, the TGFβ1 mRNA expression only increases during the decompensation stage. Urine TGFβ1 level is very high 6 weeks after BOO, which may help predict the contraction function of bladder after BOO.