家兔小肠动脉介入栓塞后对肠道平滑肌电活动的影响

Alterations in myoelectric activity of the small bowel in rabbits after transarterial embolization

目的研究介入动脉栓塞后对小肠肌电活动的影响,为小肠病变栓塞治疗后监测肠管存活和指导临床处理提供理论依据.方法20只正常家兔,分别经小肠动脉注射PVA(350～550μm)2、6mg和生理盐水2 ml,分为2 mg组(10只),6 mg组(5只)和对照组(5只).利用微导管动脉栓塞技术,以基本电节律为观察指标,研究各组动脉栓塞后24 h小肠肌电活动的改变.结果2 mg组小肠动脉PVA栓塞前后慢波频率和波幅分别为(17.83±0.55)次/min、(0.1641±0.0043)mV和(11.59±0.23)次/min、(0.0739±0.0011)mV,慢波频率和波幅明显下降(P＜0.01).6 mg组栓塞后3～6 h后基本电节律(basal electrical rhvthm,BER)活动逐渐消失,剖腹探查示肠管发生长短不等坏死.对照组小肠动脉生理盐水注射前后慢波频率和波幅分别为(17.89±0.48)次/min、(0.1632±0.0020)mV和(16.95±0.34)次/min、(0.1606±0.0030)mV,慢波频率和波幅无明显变化(P＞0.05).结论小肠动脉介入栓塞后对小肠BER影响显著,近端空肠电活动的慢波频率和波幅明显下降,小肠动脉介入栓塞后对胃肠道平滑肌慢波电活动主要表现为抑制作用,小肠动脉PVA栓塞后有望通过动态监测BER改变来判断肠壁存活与否.

Objective To explore alterations in myoeleetric activity of the small bowel in rabbits after transarterial embolization and provide academic basis for assessing bowel viability and management. Methods Twenty normal rabbits were selected and divided inlo three groups （2 mg group, n = 10; 6 mg group, n = 5;contro｜ group, n= 5）. Members of 2 mg group were embolized with PVA 2 rag, those of 6 mg group with PVA 6 mg ,and the control group with normal saline 2 ml. After microcatherization embolization, myoelectric activity of the small bowel was recorded for 24 hr using chronically implanted electrodes in conscious rabbits. Results In 2 mg group, the frequency and the amplitude of slow wave of proximal jejunum were significantly lower in post-embolization period than preembolization period [（17.83±0.55） cpm vs （11.59±0.23） cpm（P〈0.01）and （0.1641±0.0043） mV vs （0.0739±0.0011 ） mV （ P 〈 0.01 ）, respectively]. In 6 mg group, the frequency and the amplitude of slow wave of proximal jejunum showed significantly lower iu post-embolization than pre-embolization period, and the wave disappeared gradually form 3 to 6h after embolization with unequal segment necrosis of the small bowel through laparotomy. In control group, the frequeney and the amplitude of slow wave of proximal jejunum revealed no difference between pre-embolization and post-embolization period [ （ 17.89 ± 0.48） cpm vs （ 16.95 ± 0.34） epm（ P〉 0.05） and （0. 1632± 0. 002 ） mV vs （0. 1606 ± 0. 003 ） mV （ P 〉 0.05 ）, respectively ]. Conclusions Embolization with PVA evokes significant and passive effect on basal electrical rhythm of small bowel. It could provide academic basis for assessing bowel viability to interventional embolization. （J Intervent Radiol, 2005,14：409-412. ）