非胰岛素依赖型糖尿病大鼠逼尿肌兴奋性及自律性改变

Changes in excitability and autorhthmicity of bladder detrusor in rats with NIDDM

目的 研究非胰岛素依赖型糖尿病(NIDDM)大鼠的逼尿肌兴奋性及自律性的变化。方法 制作NIDDM大鼠模型,以正 常大鼠为对照,采用离体逼尿肌条研究膀胱兴奋性和自律性变化。结果 NIDDM组引起逼尿肌肌条自发收缩的张力阈值 [(0.716±0.325)g]明显高于对照组[(0.323±0.177)g](F=59.63,P<0.0001),不同时间段NIDDM组引起逼尿肌收缩的张 力阈值也高于对照组。NIDDM组逼尿肌自发收缩的频率在第6～18周的变化较对照组增高,在第22、26周较对照组减低。 结论 膀胱逼尿肌兴奋性降低是糖尿病膀胱功能最早且最明显的改变。逼尿肌自主节律性改变也是糖尿病膀胱的早期变化之一。

Objective To observe the changes of bladder detrusor excitability and autorhthmicity in experimental rats with non-insulin dependent diabetes mellitus(NIDDM). Methods Manufactured the model rats with NIDDM. At 6th,10th,14th,18th, 22nd, 26th week after the rats had been injected strepozotocin for the last time, we chose the rats at random and tested the detrusor strips in vitro. Results The threshold of tension which made the detrusor strips contract was significantly higher in the model rats (0.716±0.325g) than in the control rats (0.323±0.177g) (F= 59.63, P< 0.001). In all examinations at different stages, the threshold of tension was also higher in model rats than in the control rats. The results also showed that before 18 weeks after STZ injection the frequency of contraction of bladder detrusor in model rats was significantly higher than in the control rats (P< 0.05), whereas after 22 weeks after STZ injection, the frequency was significantly lower in the control rats than in the model rats (P< 0.05). Conclusion The decrease of excitability is the first and most obvious change in bladder detrusor of rats with NIDDM. The autorhthmicity of bladder detrusor has also changed at the early stage of diabetic cystopathy.