Pulmonary interstitial changes in pulmonary hypertension induced by high pulmonary blood flow / 中华实用儿科临床杂志

ABSTRACT

Objective To study the pulmonary interstitial changes in pulmonary hypertension induced by high pulmonary blood flow.Methods Sixty-five male or female Sprague-Dawley rats (180-230 g) were used and randomly divided into 3 groupsnormal group (n =20) ; sham group (n =20),only exposing the abdominal aorta and inferior vena cava about 10-20 minutes;model group(n =25),rats in this group were subjected to an abdominal aorta-inferior vena cava shunt to create animal models of high pulmonary.After operation,all the rats were reared under the same conditions for 11 weeks.Then,the systolic pulmonary artery pressure (sPAP) and mean pulmonary artery pressure (mPAP) of every rat were determined by means of homemade right heart catheterization.After that,the right ventricle (RV) was separated from the left ventricle (LV) and septum (S),then weighed.And right ventricular hypertrophy index (RVHI) was measured by the ratio of RV to LV + S [RV/(LV + S)].In addition,the morphological changes of pulmonary interstitial of rats were observed under optical microscope by means of hematoxylin-eosin (HE) staining.In the end,single pulmonary artery smooth muscle cell (PASMC) was isolated through acute enzyme separation.Then membrane capacitance (Cm) was recorded through in the method of patch clamp technique.Results 1.Compared with sham group and normal group,the sPAP,mPAP and RVHI of model group increased significantly(F =17.293,16.259,12.878,all P ＜ 0.01).2.In contrast to sham group and normal group,arterial wall area/vessel area(W/V) and arterial wall thickness/vessel external diameter(T/D) in model group increased significantly(F =85.717,22.795,all P ＜0.01).3.The membrane capacitance of model group was bigger than that of sham group and normal group(F =8.704,P ＜ 0.01).4.mPAP was positively correlated with W/V,T/D and Cm (r =0.669,0.662,0.663,all P ＜ 0.01).Conclusions Shunts from abdominal aorta-inferior vena cava in SD rats caused high pulmonary blood flow-induced pulmonary hypertension,and these rats appeared with pulmonary smooth muscle cells hypertrophy,pulmonary vascular wall thickening and inflammatory cells infiltration.