The Relationship between the Expression of Connective Tissue Growth Factor and Hypoxic Pulmonary Vascular Remolding in the Lung of Rats Exposed to Hypoxia

Objective:To test the role of connective tissue growth factor(CTGF)in the development of hypoxic pulmonary hypertension.Methods:Twenty male Wistar rats were divided into two groups and exposed to air and isobaric hypoxia for 3 weeks,respectively.The pulmonary artery pressure was measured by right cardiac catheterization.The expression of CTGF and collagenⅠ in the lungs of rats were measured by immunohistochemical staining.The histological sections of the lungs were examined using a computerized image analyzer.Results:The pulmonary artery pressure in the exposed rats increased.The chronic hypoxia also elicited the thicking of the wall and the narrowing of the lumen of pulmonary arterioles.It led to the increases of the pulmonary artery pressure 、the index of righr ventricular hypertrophy[RV/(LV+S)]、the ratio of vascular wall thickness/vascular external diameter(WA%)and the ratio of vascular wall area/total vascular area(WT%)compared to the controls (PAP2.89±0.41kP vs 1.37±0.26kP;﹝RV/(LV+S):41.01±2.79 vs 24.59±3.51;WT%:35.13±10.31 vs 23.66±9.74;WA%:54.18±11.46 vs 40.59±13.87 respectively,p0.05).The positive staining of CTGF and collagen Ⅰ in the wall of pulmonary arteriole of the exposed rats were significantly stronger than those of controls(P0.01).Conclusions:The CTGF may play an important role in the pathogenesis process of hypoxic pulmonary vascular remodeling and pulmonary hypertension.