Changes of bladder morphology and function and effect on upper urinary tract dilatation at different time after lumbosacral nerve transecting in rats
10.3760/cma.j.cn112330-20210714-00369
- VernacularTitle:大鼠腰骶神经离断后不同时间膀胱形态功能变化及其对上尿路扩张的影响
- Author:
Qingsong PU
1
;
Xinghuan YANG
;
Junkui WANG
;
Xiangfei HE
;
Erpeng LIU
;
Yulin HE
;
Lei LYU
;
Zhenwei ZHANG
;
Qiufang MAO
;
Qifeng DOU
;
Jianguo WEN
Author Information
1. 郑州大学第一附属医院泌尿外科 河南省小儿尿动力国际联合实验室 膀胱结构与功能重建河南省工程实验室,郑州 450052
- Keywords:
Urinary bladder, neurogenic;
Fibrosis;
Hydronephrosis;
Cystometry;
Myofibroblasts
- From:
Chinese Journal of Urology
2023;44(5):369-375
- CountryChina
- Language:Chinese
-
Abstract:
Objective:To investigate the changes in the morphology, structure and function of the bladders and their effects on the upper urinary tract dilatation(UUTD) after lumbosacral nerve transecting in rats.Methods:A total of 45 female SD rats were included, randomly divided into 3 groups with 15 rats in each group. Two groups were performed bilateral lumbar 6(L6) and cauda equina nerve shearing to establish neurogenic bladder(NB) model, which were nerve transected for 4 weeks(NB-4W) group and nerve transected for 12 weeks(NB-12W) group. Another group was performed bilateral L6 nerves and cauda equine exposing but not transecting, which was sham-operation (Sham) group. Cystometry and renal ultrasound examination were performed and rats in each group were killed to collect the kidney and bladder tissues in NB-4W group at 4 weeks, in Sham group and NB-12W group at 12 weeks after operation. HE, Masson staining, immunohistochemical staining and western blot were used to detect histological changes, expression of transforming growth factor-β1(TGF-β1) and α-smooth muscle actin(α-SMA).Results:All rats in NB-4W and NB-12W group showed acontractile detrusor. In the NB-4W and NB-12W group, the maximum cystometric capacity [(5.84±0.33) ml and (3.13±0.35) ml], the detrusor leak point pressure [(25.41±0.86) cm H 2O and (27.36±2.04) cm H 2O] (1 cm H 2O = 0.098 kPa), were significantly higher than those in the Sham group [(0.98±0.14) ml, (7.13±0.90) cm H 2O, both P<0.05]. Compliance in NB-4W group [(0.28±0.21) ml/cm H 2O] and NB-12W group [(0.17±0.12) ml/cm H 2O] were significantly lower than that of the Sham group [(0.34±0.26) ml/cm H 2O], and the compliance of NB-12W group was lower than that of NB-4W group significantly (all P<0.05). HE staining of the bladder showed that the inflammatory cell infiltration was obvious in the NB-4W and NB-12W group. Bladder collagen volume fractions in NB-4W group [(30.5±1.5) %] and NB-12W group [(45.2±3.8) %] were both higher than that of Sham group [(20.7±2.2) %, both P<0.05]. The expression of TGF-β1 and α-SMA in the bladder tissue of NB-4W group were higher than those of sham group, and that of NB-12W group were higher than NB-4W group. In NB-4W group and NB-12W group, 3 (20.0 %) and 7 (46.7 %) rats were found hydronephrosis, respectively. Additionally, HE staining showed that the degree of renal tubule injury and the number of inflammatory cell infiltration in the NB-4W and NB-12W group were higher than those in the Sham group. Masson staining showed that the volume fraction of collagen in kidneys of NB-4W and NB-12W group were (13.1±1.4) % and (21.6±1.9) %, respectively, which were significantly higher than that in sham operation group [(4.6±0.7) %, both P<0.05]. Conclusions:Bilateral L6 + cauda equina nerve transecting can induce NB with hydronephrosis in parts of rats. The degree of bladder fibrosis gradually increased with the time of nerve transection, and the incidence and severity of UUTD also increased with the time of nerve transection.