Effect of electro-acupunctare at zusanli on acute lung injury in a rat model of sepsis after scald / 中华麻醉学杂志

ABSTRACT

Objective To investigate the effect of electro-acupunctare at zusanli on acute lung injury in a rat model of sepsis after scald.Methods Fifty SPF male Sprague-Dawley rats,weighing 200-250 g,aged 2-3 months,were randomly divided into 5 groups (n =10 each) using a random number tablecontrol group (group C),sepsis after scald group (group SS),electro-acupuncture at zusanli group (group E),electric stimulation of non-acupoint group (group NE) and electro-acupuncture at zusanli + α-bungarotoxin (α-BGT,a selective α7 nicotinic acetylcholine receptor antagonist) group (group α-BGT).The rats were subjected to a third degree scald covering 20％ total body surface (TBS) and muramyl dipeptide (MDP) 5 mg/kg was injected into the femoral vein immediately after scald to induce sepsis.Electro-stimulation (3 V,2 ms,3 Hz) of bilateral zusanli was performed for 12 min starting from the time point immediately after MDP injection and every 8 h for 2 consecutive days in group E.In group NE,electro-stimulation was performed at the points 5 mm lateral to the bilateral acupoints of Zusanli and the method was similar to those previously described in group E.In group α-BGT,α-BGT 1.0 μg/kg (in 1 ml of normal saline) was injected into the femoral vein before electro-stimulation of zusanli.At 48 h after treatment,arterial blood samples were obtained for determination of serum tumor necrosis factor-alpha (TNF-α) and high mobility group box-1 (HMGB1) protein levels (by ELISA) and lung specimens were removed for microscopic examination and for determination of the expression of Nod like receptor 2 (NLR2) mRNA (by RT-PCR) and receptor interacting protein 2 (RIP2) in the lung tissues (by Western blot).Results Compared with group C,the expression of NLR2 mRNA and RIP2 was significantly up-regulated,and the serum TNF-α and HMGB1 levels were increased in SS,NE and α-BGT groups (P ＜ 0.05),and no significant change was found in the parameters mentioned above in group E (P ＞ 0.05).Compared with group SS,the expression of NLR2 mRNA and RIP2 was down-regulated,and the serum TNF-α and HMGB1 levels were decreased in group E (P ＜ 0.05),and no significant change was found in the parameters mentioned above in NE and α-BGT groups (P ＞ 0.05).Compared with group E,the expression of NLR2 mRNA and RIP2 was significantly up-regulated,and the serum TNF-α and HMGB1 levels were increased in NE and α-BGT groups (P ＜ 0.05).The pathological changes of lung tissues were significantly reduced in group E as compared with group SS.Conclusion Electro-acupunctare at Zusanli can reduce acute lung injury in a rat model of sepsis after scald and inhibition of NLR2/RIP2 signaling pathway and activation of cholinergic anti-inflammatory pathway in lung tissues may be involved in the mechanism.