Effects of endogenous sulfur dioxide on pulmonary vascular inflammation in rats with monocrotaline-induced pulmonary hypertension / 中华实用儿科临床杂志

ABSTRACT

Objective To investigate the effects of endogenous sulfur dioxide(SO2) on pulmonary vascular inflammation in rats with monocrotaline (MCT)-induced pulmonary hypertension.Methods Thirty-two Wistar rats were randomly divided into 4 groups(n =8 for each group)control group,MCT group,MCT + L-aspartic acid-β-hydroxamate(HDX) group,and MCT + SO2 group.Rats in the MCT group,MCT + HDX group,and MCT + SO2 group were subcutaneously injected with MCT(60 mg/kg) on the first day.For rats in MCT + HDX group,HDX(25 mg/kg,on day 0,7 and 14) was given orally after injection of MCT; and rats in MCT + SO2 group were subcutaneously injected with the SO2 donor sodium sulfite/sodium bisulfate(Na2SO3/NaHSO3,and mole ratio was adjusted to approximately 31) each day.Rats in the control group received only the same volume of solvent vehicle only.After 3 weeks,mean pulmonary artery pressure(mPAP) of each rat was evaluated by using a right cardiac catheterization procedure.Immunohistochemistry was used to detect the expression of inflammatory related factor intercellular adhesion molecule-1 (ICAM-1) and the key molecules of nuclear factor-κB (NF-κB) signal transduction pathway,including p65 and inhibitor of NF-κB (IκBα) in the small pulmonary artery endothelial cells.Results The differences in mPAP,expression of ICAM-1,IκBα and p65 in the small pulmonary artery endothelial cells were found among the 4 groups (mPAPF =53.334,P ＜ 0.01 ; ICAM-1F =183.82,P ＜ 0.01 ; IκBαF =142.89,P ＜ 0.01 ; p65F =105.46,P ＜0.01).The mean pulmonary artery pressure(mPAP) was significantly raised in MCT group rats as compared with that of the control group along with upregulated expressions of ICAM-1 protein and p65 protein in small pulmonary artery endothelial cells,while the expression of IκBα protein in small pulmonary artery endothelial cells was significantly low.After administration of HDX,the mPAP and the expression of ICAM-1 protein and p65 protein in small pulmonary artery endothelial cells further increased compared with those of MCT group,while the expression of IκBα protein in small pulmonary artery endothelial cells was significantly lower than that of MCT group.Whereas with treatment of SO2 derivatives,the mPAP,the expression of ICAM-1 protein and p65 protein in small pulmonary artery endothelial cells were significantly lower than those of MCT group,while the expression of IκBα protein in small pulmonary artery endothelial cells increased significantly compared with that of MCT group.Conclusions Endogenous SO2 might inhibit the activation of NF-κB pathway in the small pulmonary artery endothelial cells,attenuate the pulmonary vascular inflammation and prevent the MCT-induced pulmonary hypertension in rats.