Pulmonary protective effects of dexmedetomidine in septic rats induced by LPS / 临床麻醉学杂志

ABSTRACT

Objective To assess the role of intervention of dexmedetomidine in lung tissue and plasma of septic rats induced by lipolysaccharide.Methods Forty SD rats weighing 250-300 g were divided into 4 groupscontrol group (n =10)with saline (1 ml·kg-1·h-1 )infused through the tail veins of rats for 6 h;dexmedetomidine (DEX)group (n =10)with dexmedetomidine,injected 6.5 μg ·kg-1·h-1 for 10 min followed by 5 μg·kg-1·h-1 ,continuously infused through tail veins for 6 h;li-polysaccharide (LPS)group (n = 10 )with lipolysaccharide (7.5 mg/kg)infused through the tail veins of rats;LPS+DEX group (n =10),after infusion of LPS,rats were treated with dexmedeto-midine (bolus 6.5 μg·kg-1·h-1 ,10 min;5 μg·kg-1·h-1 ,continuous infusion)through the tail veins for 6 h.ELISA and Western blot were performed to assess the protein expression of IL-1,IL-6, TNF-αand TLR4;the wet/dry ratio (W/D)of lung tissue in each group was measured and the injury scores were recorded through the Murakami method.Results There was no statistical significance between the control group and DEX group in plasma level of inflammatory factors,pulmonary TLR4 expression,wet/dry ratio and injury score of lung tissues,however,compared to the control group, there was a significant elevation in the above-mentioned biomarkers,W/D and injury score of lung tis-sue (P <0.01).Compared to the control group,there was no statistical significance in the LPS+DEX group.Compared to the LPS+DEX group,the biomarkers mentioned above,W/D and injury score of lung tissues were significantly elevated in the LPS group (P <0.01).Conclusion The irrita-tion of LPS can trigger the elevation of inflammatory factors in plasma,TLR4 expression in lung tis-sues in rats,while the intervention of dexmedetomidine can significantly alleviate this tendency. Dexmedetomidine can suppress the inflammatory reaction and pulmonary edema in septic rats.