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

ABSTRACT

Objective To evaluate the effect of electro-acupunctare at Zusanli on liver 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); electro-acupuncture at Zusanli + α-bungarotoxin (α-BGT) group (group α-BGT).The rats were subjected to a third degree scald covering 20％ of the total body surface area (TBSA) and sepsis was induced with muramyl dipeptide (MDP) 5 mg/kg injected into the femoral vein immediately after scald.Electro-stimulation (3 V,2 ms,3 Hz) of bilateral Zusanli acupoints or non-acupoints was performed for 12 min every 8 h for 2 consecutive days starting from the time point immediately after MDP was injected in group E.In group NE,electro-stimulation was performed at the points 5 mm lateral to the acupoints of bilateral Zusanli and the method was similar to those previously described in group E.In group α-BGT,α-BGT 1.0 μg/kg (in normal saline 1 ml) was injected into the femoral vein before electric stimulation,then electro-stimulation was performed and the method was similar to those previously described in group E.After 48 h of continuous stimulation,liver specimens were obtained for microscopic examination of the pathological changes.The blood samples were obtained from the abdominal aorta for determination of the levels of serum ALT and AST,tumor necrosis factor-alpha (TNF-α),and high mobility group box-1 (HMGB1) (by ELISA),and expression of Nod-like receptor 2 (NLR2) mRNA (by RTPCR) and receptor-interacting protein 2 (RIP2) in the liver tissues (by Western blot).Results The serum ALT and AST,TNF-α and HMGB-1 levels and NLR2 mRNA and RIP2 expression in liver tissues were significantly higher in SS group than in C group.Compared with SS group,the serum ALT,AST,TNF-α and HMGB1 levels were significantly decreased and NLR2 mRNA and RIP2 expression was down-regulated in E group,and no significant changes were found in the parameters mentioned above in NE group.Compared with E group,the serum ALT,AST,TNF-α and HMGB1 levels were significantly increased,and NLR2 mRNA and RIP2 expression was up-regulated in α-BGT group.The pathological changes in liver tissues were significantly reduced in group EA as compared with SS,NE and α-BGT groups.Conclusion Electro-acupuncture at Zusanli can reduce liver injury in a rat model of sepsis after scald and inhibition of NLR2/RIP2 signaling pathway and activation of cholinergic antiinflammatory pathway mediated by α7 nicotinic acetylcholine receptors in liver tissues may be involved in the mechanism.