Effects of electroacupuncture at Zusanli points on gut permeability in rats with intestinal ischemia/reperfusion injury / 中国中西医结合急救杂志

ABSTRACT

Objective To investigate the protective effects of elctroacupuncture(EA)at Zusanli(ST36) points on intestinal villas damage and mucosal permeability induced by small intestine pro-inflammatory factors in rats with intestinal ischemia/reperfusion(I/R). Methods 30 Sprague-Dawley(SD)rats were randomly divided into three groups(each,n=10):intestinal I/R group(model group),intestinal I/R+EA ST36 group(EA group)and intestinal I/R+sham EA group(SEA group). Rats were subjected to superior mesenteric artery(SMA)clamping at its root part to occlude the vessel for 30 minutes,followed by reperfusion for 60 minutes to form intestinal I/R models. Rats in EA group received EA at the bilateral ST36 points(2-3 mA,2-100 Hz)for 30 minutes immediately after ischemia,those in SEA group received EA at bilateral sham points(the point was located at 0.5 cm away from ST36 point in its lateral side)with the same frequency and intensity of stimulation as EA group for 30 minutes,and those in model group received no treatment. Animals were sacrificed 60 minutes after reperfusion and segments of distal part of ileum were harvested,then the levels of tumor necrosis factor-α(TNF-α)and interleukin-6(IL-6)in intestinal tissue were measured. Histopathologic changes were viewed and graded via light microscopy. A solution of fluorescein isothiocyanate(FITC)-dextran was injected into the lumen of the segment of intestine 30 minutes after reperfusion,systemic blood was drawn via abdominal aorta puncture at 60 minutes after reperfusion,and then the level of FITC-dextran in blood was measured to determine the changes in intestinal permeability. Results Compared to the model group and SEA group,EA ST36 significantly attenuated intestine TNF-α(pg/mg:3.01±0.50 vs. 8.65±1.02,8.42±1.41,both P0.05). Sections of distal ileum from animals in the model group and SEA group showed no obvious difference histologically,and the pathological manifestations were villous tip necrosis, blunt-shaped and collapse. Compared to the model group and SEA group,the intestinal villous injury in animals of EA group was much milder. Conclusion In rats with intestinal I/R injury,EA ST36 points has protective effect on the gut that is possibly due to the fact it may obviously lower the levels of the pro-inflammatory factors of small intestinal tissue,alleviate mucosal insult of gut and reduce the mucosal permeability.