Effect of low-dose paclitaxel on morphology of bladder in rats with infra-vesical obstruction / 中国病理生理杂志

ABSTRACT

AIM: To investigate the effects of low-dose paclitaxel on the morphology of bladder after partial bladder outlet obstruction ( BOO) in rats.METHODS:Healthy female Sprague-Dawley rats ( n=30) were randomly di-vided into sham operation group, BOO group and low-dose paclitaxel group.The rats in BOO group and low-dose paclitaxel group received operation to establish an obstruction model, while the rats in sham group underwent sham operation.After operation, the rats in low-dose paclitaxel group received intraperitoneal injection of paclitaxel at a dose of 0.3 mg/kg twice a week for 4 weeks.At the same time, the animals in sham group and BOO group received the same volume of saline by in-traperitoneal injection.Four weeks after operation, each rat was sedated and the bladder was weighted.Histological chan-ges of the bladder were observed by HE staining.Collagen deposition in the bladder tissue was observed by Masson stai-ning, and the fibrosis area was measured.The ultrastructure of the detrusor was studied by transmission electron microsco-py.RESULTS:Compared with sham operation group, a significant increase in bladder weight (0.376 g ±0.052 g vs 0.112 g ±0.014 g, P<0.05), the muscle hypertrophy, and a decrease in the percentage of collagen area [collagen/(col-lagen+muscle), 29.66%±2.69%vs 38.94%±3.67%, P<0.05] was observed in BOO group.Under electron micro-scope, intracellular connection had more gap junction and desmosomes than intermediate junction.The cell gap widened with a large amount of collagen fiber.Compared with BOO group, low-dose paclitaxel group decreased bladder weight (0.215 g ±0.025 g vs 0.376 g ±0.052 g, P<0.05) and improved the muscle hypertrophy.The percentage of the colla-gen area was also decreased (19.94%±1.90% vs 29.66%±2.69%, P<0.05).The detrusor microstructure showed that the intermediate junction was characterized by a predominance among the intracellular connections, and the intercellu-lar space contained less collagen fibers in low-dose paclitaxel group.CONCLUSION:Low-dose paclitaxel may ameliorate the morphological damage of the bladder and recover bladder function in the rats with BOO by slowing down the process of bladder fibrosis.