Aim: To study the expression of vascular endothelial growth factor (VEGF) and proliferating cell nuclear antigen(PCNA) in aorta and pulmonary artery smooth muscle cells of rats with hypoxia pulmonary hypertension(HPH).
Methods: The rat chronically HPH models were set up in the hypobaric hypoxia cabin. The experimental rats were divided into 3 groups: control group (rearing in a normoxia environment), two hypoxia groups (oxygen-deficient time being 2 weeks and 3 weeks, respectively). Expression of VEGF and PCNA were detected by immunohistochemical staining and image analysis.
Results: There was VEGF expression in vascular smooth muscle cells of aorta, pulmonary artery trunk and pulmonary arteriole in control group. In two hypoxia groups VEGF expression in vascular smooth muscle cells of pulmonary artery, trunk and pulmonary arteriole increased significantly, while no difference was found in smooth muscle cells of aorta. Expression of PCNA was very little in vascular smooth muscle cells of aorta, pulmonary artery trunk and pulmonary arteriole in control group. In two hypoxia groups, the PCNA expression increased only in vascular smooth muscle cells of pulmonary arteriole; there was no difference of PCNA expression in vascular smooth muscle cells of aorta and pulmonary artery trunk between hypoxia groups and control group.
Conclusion: There is difference of VEGF expression in pulmonary artery trunk and aorta smooth muscle cells during the formation of chronic HPH, suggesting that VEGF expression may play very important role in the formation of chronic HPH.