The Effects Of Dexmedetomidine On Abdominal Adhesions In Rats And The Role Of Cholinergic Anti-inflammatory Pathway

Objective To evaluate the effect of dexmedetomidine on abdominal adhesion and the role of cholinergic anti-inflammatory pathway.Methods Forty clean male SD rats weighing 220-250 g were randomly divided into four groups(n=10): Sham operation group(Sham group),Adhesion Model group(M group),Dexmedetomidine group(DEX group)and Dexmedetomidine + Methylniubinine group(DEX-M group),The abdominal adhesion model of rats in M group,DEX group and DEX-M group was established by cecal friction method,while in Sham group,only abdominal cavity was opened without cecal friction.Before abdominal closure,In Sham group?M group,2ml normal saline was injected into abdominal cavity and tail vein respectively.The DEX group and DEX-M group were respectively injected with 2ml normal saline and 2.4 g/g(soluble in 2ml normal saline)in the tail vein,and at the same time,Dexmedetomidine 10 ?g/kg(soluble in 2ml normal saline)in the abdomen.7 d after modeling,Phillips method was used for the formation of abdominal adhesion scoring.ELISA was used to detect the transforming growth factor-beta1(TGF-beta1)and serum Tumour necrosis factor-alpha(TNF-alpha)concentrations in ascites.The rats were then sacrificed,and the caecum tissue and its contralateral peritoneum and adhesion fibrous strips were taken.HE staining was used to observe the pathological changes of cecum and peritoneum under light microscope(×100),and Masson staining was used to observe the formation of collagen fibers in adhesive tissue(×100).Results Compared with group Sham,the abdominal adhesion score of group M and group DEX-M increased(P<0.05),the concentration of TGF-?1 in ascites of group M,group DEX and group DEX-M increased(P<0.05),and the concentration of serum TNF-? in group M and group DEX-M increased(P<0.05),a large number of neutrophils infiltrated in cecum and peritoneum,and collagen fibers in adhesive zone proliferated significantly;compared with group M,the abdominal adhesion score of group DEX decreased(P<0.05),the abdominal adhesion score of group DEX-M had no statistical significance(P>0.05),the serum TNF-? and ascites TGF-?1 concentration of group DEX and group DEX-M decreased(P<0.05),the infiltration of neutrophils in cecum and peritoneum was alleviated,and the proliferation of collagen fibers in adhesive zone was not obvious;compared with the group DEX,the serum TNF-? concentration of group DEX-M increased(P<0.05),the ascites TGF-?1 concentration had no statistical significance(P>0.05).Conclusion Intraperitoneal injection of Dexmetomidine can alleviate abdominal adhesion in rats,and its mechanism is related to the activation of cholinergic anti-inflammatory pathway and the reduction of systemic inflammation.