Effect of electro-acupuncture at Zusanli acupoint on blood coagulation during intestinal ischemia-reperfusion in rats

Abstract

Objective To evaluate the effect of electro-acupuncture (EA) at Zusanli (ST36) acupoint on blood coagulation during intestinal ischemia-reperfusion (I/R) in rats. Methods Forty healthy male Sprague-Dawley rats, aged 6-8 months, weighing 250-300 g, were divided into 5 groups (n=8 each) using a random number table: sham operation group (group S), intestinal I/R group (group I/R), EA at Zusanli acupoint group (group EA), EA at non-acupoint group (group NE) and α7 nicotinic acetylcholine receptor antagonist α-bungarotoxin (α-BGT) group (group α-BGT). Intestinal I/R was induced by clamping the superior mesenteric artery for 45 min followed by 120 min of reperfusion.Bilateral Zusanli acupoints were stimulated with an electric stimulator (frequency 3 Hz, voltage 2-4 V, wave length 2 ms) for 30 min starting from the time point immediately after beginning of ischemia in group EA, while EA was performed at the points 5 mm lateral to the bilateral Zusanli instead in group NE.In group α-BGT, α-BGT 1 μg/kg was intraperitoneally injected at 45 min before ischemia, and the other treatments were similar to those previously described in group EA.Blood samples were collected from the abdominal aorta at 120 min of reperfusion for determination of the concentrations of tumor necrosis factor alpha (TNFα), tissue factor (TF), antithrombin (AT), tissue plasminogen activator (tPA), fiber plasminogen activator inhibitor-1 (PAI-1) and D-dimer in plasma (by enzyme-linked immunosorbent assay) and platelet count (PLT). The animals were sacrificed after blood sampling, the distal ileum specimens were removed for examination of the pathological changes with a light microscope, and the damage to the intestinal mucous membrane was assessed and scored according to Chiu. Results Compared with group S, the concentrations of plasma TNFα, TF, tPA, PAI-1 and D-dimer were significantly increased, and the plasma AT concentration and PLT were decreased in I/R, NE and α-BGT groups, the concentrations of plasma TNFα and TF were significantly increased, and the plasma AT concentration was decreased in group EA, and Chiu′s scores were significantly increased in I/R, EA, NE and α-BGT groups (P 0.05). Compared with group EA, the concentrations of plasma TNFα, TF, tPA, PAI-1 and D-dimer were significantly increased, the plasma AT concentration and PLT were decreased, and Chiu′s scores were increased in group NE (P<0.05). Conclusion EA at Zusanli acupoint can improve blood coagulation during intestinal I/R in rats, and the mechanism is related to activating the cholinergic anti-inflammatory pathway. Key words: Electroacupuncture; POINT ST36 (ZUSANLI); Reperfusion injury; Intestines; Blood coagulation