Study On The Dose-effect Relationship Of Ambroxol Pretreatment On Acute Lung Injury In Rats

OBJECTIVE: To study the dose-effect relationship of different doses of ambroxol on lung protection induced by lipopolysaccharide(LPS)in rats with acute lung injury(ALI).METHODS: 56 SD rats were randomly divided into 7 groups(n = 8): blank control group,lipopolysaccharide control group,ambroxol 10 mg / kg treatment group,ambroxol 20 mg / kg treatment group,ambroxol 30 mg / kg treatment group,50 mg / kg treatment group and ambroxol 50 mg / kg treatment group.ALI rat model was established by intraperitoneal injection of LPS(5mg / Kg).The blank control group was treated with normal saline,and the corresponding dose of Misartan was injected to other groups through the tail vein once a day for 3 days.After 30 minutes of the last injection LPS(5mg / Kg)was injected intraperitoneally to establish ALI rat model.Rats were sacrificed 6 hours after injection and lung tissue was removed.The lung tissue histopathological changes were observed by HE staining and then we measured The wet / dry weight ratio(W / D)of lung tissue.TNF-?,IL-1?,IL-6 in lung tissue homogenate were detected by ELISA.Results: The ratio of W / D,TNF-?,IL-1? and IL-6 in LPS control group and each dose group were significantly higher than those in blank control group(P <0.05).The W/D ratio,TNF-?,IL-1?and IL-6 levels in each dose-treated group were significantly lower than those in the LPS control group(P <0.05);W/D ratio,TNF-?and IL-1?of40mg/kg treatment group were significantly decreased compared to10,20,30mg/Kg dose group,but the level of IL-6 was not significantly decreased(P> 0.05),The levels of W/D ratio,TNF-?,IL-1? and IL-6 of50mg/Kg group were not significantly improved than those in other groups(P> 0.05).Conclusion: 1.Intravenous administration of high-dose ambroxol in a certain dose range of LPS-induced acute lung injury has a protective effect,but to 50 mg / Kg when the protective effect is no further enhanced 2.The protective effect of high dose ambroxol on LPS-induced acute lung injury was dose-dependent in a certain range.