温度对大鼠离体逼尿肌肌条自发性收缩功能的影响

Effects of temperature on the spontaneous contraction function of detrusor muscle strips of rats in vitro

目的探讨温度对膀胱逼尿肌肌条自发性收缩的影响。方法建立膀胱出口梗阻(BOO)模型,6周后行充盈性膀胱测压确诊稳定膀胱(DS)组和不稳定膀胱(DI)组。制备膀胱逼尿肌肌条并在32～37、21～31、15～20、4～14℃等不同条件下Krebs营养液中给予特定的前负荷进行逼尿肌肌条实验。结果成功建立BOO模型。逼尿肌肌条在32～37、21～31℃Krebs营养液中出现自发性收缩波的前负荷为0.3 g,15～20℃Krebs营养液中出现自发性收缩波的前负荷为1.0 g,4～14℃Krebs营养液中未出现收缩波,肉眼观察肌条呈团状。32～37℃Krebs营养液中的对照组、DS组和DI组离体逼尿肌肌条收缩频率高于21～31、15～20℃Krebs营养液中相应各组的收缩频率(P<0.05),对照组和DI组在21～31℃Krebs营养液中的逼尿肌肌条收缩频率高于15～20℃Krebs营养液中收缩频率(P<0.05)。3组逼尿肌肌条在32～37、21～31、15～20℃Krebs营养液中收缩幅度比较,差异均无统计学意义(P>0.05)。结论逼尿肌肌条在15～20℃Krebs营养液中兴奋性较低,不易诱发或加重膀胱逼尿肌无抑制性收缩;在4～14℃Krebs营养液中处于持续收缩状态。根据离体逼尿肌肌条在不同温度下的收缩特性,为减少良性前列腺增生术后膀胱痉挛的次数和程度,15～20℃是持续膀胱冲洗液的适宜温度。

Objective To probe into the effects of the temperature on the spontaneous contraction of detrusor muscle strips. Methods Animal models of bladder outlet obstruction（BOO） were established,followed by a filling cystometry to screen the detrusor stability（DS） group and detrusor instability（DI） group after six weeks.Bladder detrusor muscle strips were made and tested in Krebs nutritional fluid with different temperature,that was 32-37,21-31,15-20,4-14 ℃,and given preload. Results BOO model was successfully established.The preload of betrusor muscle strips which could induce the spontaneous contraction waves in 32-37 ℃ and 21-31 ℃ Krebs nutritional fluid was 0.3 g,the preload which could induce the spontaneous contraction waves in 15-20 ℃ Krebs nutritional fluid was 1.0 g,there was no spontaneous contraction waves showed in 4-14 ℃ Krebs nutritional fluid,but by the naked eye,the muscle strips showed clumps.The contraction frequencies of detrusor muscle strips in control group,DS group and DI group in 32-37 ℃ Krebs nutritional fluid were higher than those in 21-31 ℃ and 15-20 ℃ Krebs nutritional fluid（P0.05）.The contraction frequencies in control group and DI group in 21-31 ℃ Krebs nutritional fluid were higher than that in 15-20 ℃ Krebs nutritional fluid（P0.05）.But there were no statistical significance in the contraction tension of the muscle strips in 32-37,21-31 and 15-20 ℃ Krebs nutritional fluid in three groups（P0.05）. Conclusion The excitability of detrusor muscle strips in 15-20 ℃ Krebs nutritional fluid is lower.It is no easy to induce or aggravate the uninhibited contraction of bladder detrusor muscle.Isolated detrusor muscle strips in 4-14 ℃ Krebs nutritional fluid are in a continuous contraction state.According to contraction function of isolated detrusor muscle strips in the different temperature,the optimum temperature of bladder flush fluid is 15-20 ℃ in order to decrease the chances and degree of bladder convulsion after benign prostatic hyperplasia operation.