盐酸右美托咪定对脓毒症急性肺损伤小鼠基质金属蛋白酶7抑制作用研究

目的:探讨右美托咪定对脓毒症急性肺损伤(ALI)小鼠基质金属蛋白酶7(MMP7)的抑制作用.方法:制备脓毒症致ALI模型,将昆明小鼠随机分为对照组和ALI组及治疗组,每组32只;损伤组及治疗组腹腔注射大肠杆菌脂多糖10 mg/kg,治疗组在注射脂多糖后给予腹腔注射右美托咪定25μg/kg,对照组仅注射等剂量生理盐水,并...

Inhibitory effect of dexmedetomidine on serum matrix metalloproteinase 7 in mice with septic acute lung injury

Objective:To evaluate the inhibitory effect of dexmedetomidine on matrix metalloproteinase 7（MMP7） in mice with septic acute lung injury. Methods: The sepsis-induced acute lung injury animal model was established，and KM mice were randomly divided into control group，acute lung injury（ALI） group，and treatment group，with 32 mice in each group. The mice in injury group and treatment group were injected E.coli lipopolysaccharide（LPS） 10 mg/kg through intraperitoneal administration，the treatment group was given intraperitoneal injection of dexmedetomidine 25 μg/kg after lipopolysaccharide injection，and the control group was injected with the same dose of normal saline，and each group were divided into 4 subgroups according to different injury time points:1 h，3 h，5 h，8 h. After reaching the corresponding time point，when the mice were completely anesthetized，blood was taken from the inner canthus，and the serum was centrifuged at low temperature for reserve，the changes of MMP7 was measured. The lower lobe of the right lung was left for hematoxylin and eosin（HE） staining，and the lung tissue was removed and placed in 10% formalin solution. The middle and upper lobe tissues of the right lung were homogenized to extract protein，and the left lung tissue was immersed in 2.5% glutaraldehyde for electron staining. Results:In the treatment group，inflammatory cell exudation decreased，while in the ALI group，lung structure was severely damaged and inflammatory cell exudation increased. The injury of pulmonary vascular endothelial cells was observed by electron microscopy，and the injury degree of vascular endothelial cells in the treatment group was less than that in the ALI group. The serum concentration of MMP7 in the treatment group was lower than that in the ALI group. The concentration of serum MMP7 in control group and treatment group was lower than that in ALI group. There was statistically significant difference among each group（P<0.01）. Western blotting showed that the expression of MMP7 was higher in ALI group at 3 h after injury. The expression of MMP7 in the treatment group was lower than that in the ALI group（P<0.01）. Conclusion:Dexmedetomidine can suppress the expression of serum MMP7 in mouse model of ALI caused by sepsis to a certain extent.