胆汁酸肠肝循环对消化间期移行性复合运动的作用

Effect of bile acid enterohepatic circulation on interdigestive migrating motor complex

目的:探讨胆汁酸肠肝循环对消化间期胃肠移行陛复合运动(MMC)的影响. 方法:建立狗胆汁酸体外循环模型(n=12),观察在胆汁酸肠肝循环完整、胆汁体外引流及自体胆汁回输时MMC及血浆胃动素(MTL)浓度的变化. 结果:正常狗小肠MMC有3个不同的时相;Ⅲ相时MTL水平较Ⅰ相明显增高(433.8±46.3ng/L vs112.6±21.7ng/L, P=0.000<0.01).胆汁体外引流时,MMC周期明显延长(110.2±13.6 min vs 99.1±14.4 min,P=0.001<0.01), 无Ⅲ相活动,Ⅰ相缩短(31.0±6.6min vs 53.2±9.2min, P=0.002<0.01),Ⅱ相延长(79.2±11.8 min vs 41.3±9.9 min,P=0.001<0.01),Ⅱ相末30 min的动力指数较正常时降低(41.3±6.8 mV/s vs 69.1±9.2 mV/s vs. P=0.001<0.01);而MTL在各监测点间无明显变化.自体胆汁回输后,仍无明显的MMC Ⅲ相活动,与灌输前比较, MMC周期缩短(101.9±14.0 min vs 110.2±13.6 min. P=0.03<0.05),Ⅰ相延长(44.1±6.3 min vs 31.0±6.6 min,P=0.002<0.01),Ⅱ相缩短(57.9±10.7 min vs 79.2±11.8 min,P=0.002<0.01),Ⅱ相末30 min的动力指数较引流前明显增高(59.4±7.6 mV/s vs 41.3±6.8 mV/s, P=0.002<0.01),接近正常的MMC特征;而血浆MTL水平仍无明显变化. 结论:胆汁酸肠肝循环对维持MMC有重要意义,MTL可能发挥着重要的中介作用.

AIM: To investigate the effects of enterohepatic circulation of bile acid on interdigestive migrating motor complex (MMC). METHODS: The dog models of extracorporeal circulation of bile acid were established firstly (n =12). Then the records of MMC were observed with bile flow intact, during total external biliary diversion and after re-infusion of the bile into the dogs' duodenum respectively. At the same time, the concentration of plasma motilin (MTL) was measured under different conditions. RESULTS: The interdigestive MMC with bile flow intact included 3 phases. The concentration of plasma MTL cycled with MMC. The level of MTL in phase Ⅲwas much higher than that in phase Ⅰ (433.8±46.3 ng/L vs 112.6±21.7 ng/L, P= 0.000<0.01). During total external biliary diversion, phase Ⅲ was not obvious. Compared with the normal period of MMC, the one during total external biliary divevsion was much longer (110.2±13.6 min vs 99.1±14.4 min, P=0.001<0.01); the duration of phase Ⅰ was shorter (31.0±6.6 min vs 53.2 ?9.2 min, P=0.002<0.01) and that of phase Ⅱ was longer (79.2±11.8 min vs 413±9.9 min, P= 0.001<0.01). The dynamic index of last 30 min of phase Ⅱ was lower than that of normal (41.3±6.8 mV/s vs 69.1±9.2 mV/s, P= 0.001<0.01). At the same time, the concentrations of plasma MTL did not show significant differences with the changing of MMC. Phase Ⅲ was also not obvious after re-infusion of the bile. However, compared with pre-infusion, the characteristics of MMC changed and were more similar to normal MMC. CONCLUSION: Enterohepatic circulation of bile acid plays an important role in the maintenance of interdigestive MMC. MIL is an important factor in the initiation of phase Ⅲ of MMC.