Effects of ghrelin on pulmonary capillary permeability in rats with acute lung injury caused by endotoxin

doi:10.3969/j.issn.1002-1949.2014.10.018

Abstract：Objective To observe the effects of ghrelin on pulmonary capillary permeability of acute lung injury ( ALI) caused by LPS.Methods Male SD rats were randomly divided into three groups:saline control group which received normal saline , ALI group which received LPS (5 mg/kg) to induce ALI model, Ghrelin therapy group were intraperitoneally injected with ghrelin (40 nmol/kg) 30 min after LPS challenge.Rats were sacrificed at 6 h after LPS injection.Arterial blood was collected for determination blood gas . Lung tissue was removed and the right lung was lavaged to collected bronchoalveolar lavage fluid ( BALF) for determination of protein content , and differential inflammatory cell counts . The left lung was used for microscopic examination , wet/dry lung weight ratio , myeloperoxidase (MPO) activity and Evans Blue (EB) content.Results In ghrelin therapy group, lung weight ratio , EB content and W/D ratio in lung tissue were significantly reduced compared with those in ALI group (P <0.05).The total and differential inflammatory cells were also significantly reduced in ghrelin therapy group which compared with ALI group .The level of PaO 2 of ghrelin therapy group was increased significantly compared with ALI group (P<0.01), the level of PaCO2 decreased significantly compared with ALI group ( P <0.05 ), and the value of pH was significantly higher compared with ALI group (P<0.05).Pathological examination showed that the lung injuries of ghrelin therapy group were significantly reduced compared with those of ALI group .Conclusion Ghrelin shows a marked reductive effect on the capillary permeability , reduce the injury of lung tissue and exert protective effects on lung in ALI rats .