Effect of dexmedetomidine on intestinal injury in rats with endotoxemia / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the effect of dexmedimidine on intestinal injury in rats with endotoxemia.Methods Twenty-four healthy adult male Sprague-Dawley rats,aged 2-3 months,weighing 200-250 g,were divided into 4 groups (n =6 each) using a random number table method:control group (group C),endotoxemia group (group E),dexmedimidine group (group D) and dexmedimidine plus α7 subunit-containing nicotinic acetylcholine receptor antagonist group (D +α-BGT group).The endotoxemia model was established by injecting lipopolysaccharide (LPS) 10 mg/kg via the femoral vein.Dexmedetomidine 40 μg/kg was injected and 15 min later LPS was intravenously injected in group D.Dexmedetomidine 40 μg/kg was intraperitoneally injected after intraperitoneal injection of α-bungarotoxin 1 μg/kg,and 15 min later LPS was intravenously injected in group D+o-BGT.Blood samples were collected from the abdominal aorta at 6 h after LPS injection for determination of the plasma interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α) concentrations (by enzyme-linked immunosorbent assay).Rats were sacrificed after blood sampling,and intestinal tissues were obtained for examination of the pathological changes and for determination of the myeloperoxidase (MPO) activity (by chemical colorimetry) and expression of NF-κB p65 in nucleoprotein (by Western blot).Results Compared with group C,the plasma IL-6 and TNF-o concentrations and MPO activity in intestinal tissues were significantly increased,and the expression of NF-κB p65 in nucleoprotein was up-regulated in the other 3 groups (P＜0.05).Compared with group E,the plasma IL-6 and TNF-α concentrations and MPO activity in intestinal tissues were significantly decreased,the expression of NF-κB p65 in nucleoprotein was down-regulated (p＜0.05),and the pathological changes of intestinal tissues were significantly attenuated in group D.Compared with group D,the plasma IL-6 and TNF-α concentrations and MPO activity in intestinal tissues were significantly increased,the expression of NF-κB p65 in nucleoprotein was up-regulated (P＜0.05),and the pathological changes of intestinal tissues were accentuated in group D+α-BGT.Conclusion Dexmedetomidine can reduce the intestinal injury in rats with endotoxemia,and the mechanism may be related to activating cholinergic anti-inflammatory pathway and further inhibiting inflammatory responses.