神经营养因子-3对大鼠胃肠肌电活动的影响

目的　探讨进行人重组神经营养因子 3(rh NT 3)对大鼠胃肠动力及消化间期移行性复合肌电 (MMC)的影响。方法　在大鼠的胃窦、十二指肠、空肠及结肠处手术埋植银丝电极 5～ 7d后 ,在清醒空腹状态下通过尾静脉注射2 0 μg·kg- 1 的rh NT 3或安慰剂 ,对照分析注射前后各 2h大鼠的胃肠肌电活动变化。结果　rh NT 3对胃窦及小肠处的肌电活动有增强效应 (P <0 .0 5 ) ,但对其MMCs周期无显著影响 ;在横结肠 ,rh NT 3不但可显著增强峰电的频率、振幅及延长峰电周期 ,而且可以使MMCs周期延长 (2 5± 11)minvs.(19± 6 )min ,P <0 .0 5 ) ];在远端结肠处 ,rh NT 3打断MMC模式 ,引起类似MMCⅢ相的连续的峰电活动 ,持续约 (48± 6 )min。结论　外源性的rh NT 3对大鼠的胃肠肌电活动具有加强作用

Effects of human recombinant neurotrophin-3 on the gastrointestinal myoelectric activity in rats

Objective To observe the effects of human recombinant neurotrophin-3 (rh-NT-3) on the gastrointestinal motility and the migrating myoelectric complex (MMC) in rats. Methods Five to seven days after we chronically implanted bipolar silver electrodes on the stomach, duodenum, jejunum and colon, the experimental rats were injected with rh-NT-3 via tail vein at a dose of 20?μg·kg -1 and the gastrointestinal myoelectrical activity was recorded before and after 2 hours of the test substance infusions on these conscious fasting rats. Results In the gastric antrum and intestine, rh-NT-3 had increasing effects on demographic characteristics of the electrical activities (P<0.05) except that it did not affect the intervals of MMCs. In the transverse colon, rh-NT-3 could significantly increase the frequency, amplitude and duration levels of spike bursts, and also could prolong the intervals of MMC (25±11)?min vs (19±6)?min, P<0.05]. In the distal colon, rh-NT-3 could evoke phase Ⅲ-like activity and disrupt the MMC pattern, which was replaced by a continuous long spike bursts (LSB) and irregular spike activity (ISA) for (48±6)?min. Conclusion Exogenous rh-NT-3 can stimulate gut myoelectric activity in rats.