钙通道阻滞剂对大鼠离体不稳定逼尿肌收缩性和自律性的影响

Effect of calcium channel blocker on the contractility and autorhythmicity of isolated instable detrusor strip in rats

目的探讨L型、T型钙通道阻滞剂对膀胱出口梗阻(bladder outlet obstruction,BOO)引起的不稳定逼尿肌的收缩性、自律性的影响。方法建立SD雌性大鼠BOO动物模型,6周后行充盈性膀胱测压及离体逼尿肌条机械牵拉、钙通道阻滞剂刺激试验。结果BOO后逼尿肌不稳定(detrusor instability,DI)的发生率为75.9%;DI组与正常对照组相比,收缩性、自律性明显升高,收缩力增强;正常对照组、DI组逼尿肌条在L型、T型钙通道阻滞剂作用下,自律性、收缩力均明显降低,其中正常组更明显(P<0.05)。结论DI的发生与逼尿肌自身的钙通道数量表达和功能改变有密切关系。

Objective To investigate the effect autorhythmicity, contractility in order to elucidate the of L-type and T-type calcium channel blocker on detrusor pathogenesis of detrusor instability （DI）. Methods Animal models of bladder outlet obstruction （BOO） were established in 33 female SD rats and another 10 served as normal control. Six weeks later, the changes of detrusor autorhythmicity and contractility were examined by means of cystometry and the in vitro detrusor strip study. Results The incidence rate of DI was 75.9%. The detrusor autorhythmicity and contractility increased evidently after BOO （ P 〈0. 05 ）. Both Nifedipine and NiC12 decreased the contractility and the frequency of the spontaneous contraction of detrusor strip in DI rats and normal controls of which the changes were more significant （ P 〈0. 05 ）. Conclusion The mechanism of DI is closely related to the changes in function and quantity of calcium channels.