ATP对正常及DI大鼠离体逼尿肌肌条自发性收缩的影响

Effects of ATP on normal and instability detrusor smooth muscle strips of rat in vitro

目的初步探讨ATP对正常及DI大鼠离体逼尿肌肌条自发性收缩的影响。方法通过建立大鼠逼尿肌不稳定模型,采用离体逼尿肌肌条实验观察ATP对正常及DI大鼠逼尿肌收缩特性的影响。结果成功建立了稳定的大鼠DI模型,成功率76·67%。DI组离体逼尿肌肌条自发性收缩频率及收缩力明显高于对照组;ATP可以明显加快DI组逼尿肌肌条自发性收缩频率,而对收缩力无明显影响。结论ATP主要调节大鼠逼尿肌兴奋性方面,而在收缩力方面可能不起重要作用。

Objective To study the effects of ATP on normal and instability detrusor smooth muscle strips of rat in vitro. Methods Bladder outlet obstruction was established in 40 female Wistar rats by ligating the proximal urethra in the perineum for 6 weeks. Another 20 female rats served as control. The alterative frequency of spontaneous contraction of isolated control and instable detrusor smooth muscle strips underwent the modulation of ATP was studied. Results Reflex micturition remained in conscious rats during in vivo cystometric evaluation. There were 76.67% obstructed rats that developed DI. Detrusor smooth muscle strips produced spontaneous contraction under a certain preload and the frequency significantly increased in DI group as compare with control. ATP elevated the contraction frequency of both control and DI detrusor smooth muscle strips with a greater alterative range in DI group. ATP could also influence the contraction tension of the detrusor strips, but without statistic difference. Conclusion ATP plays a very important role in the excitability but not in contraction tension on rat detrusor.