苏拉明对慢性低氧高二氧化碳大鼠血管内皮生长因子的影响

目的　探讨血管内皮生长因子 (VEGF)在低氧性肺动脉高压形成中的意义及苏拉明对其的影响。方法　将 30只SD大鼠分成正常对照组 (N组 )、低O2 高CO2 4wk组 (F组 )、低O2 高CO2 4wk +苏拉明组 (S组 ) ,采用ELISA法、透射电镜、免疫组化和原位杂交技术等方法 ,观察各组大鼠肺动脉平均压 (mPAP)、右心室重量比 (RV/LV +S)、血清和肺组织VEGF含量、肺细小动脉超微结构、肺组织VEGF及其基因表达的变化。结果　①F组大鼠mPAP、RV/LV +S、血清和肺组织VEGF的含量高于N组 (P <0 0 1) ,S组大鼠mPAP、RV/LV +S、血清VEGF低于F组 ,(P <0 0 1) ,而肺组织VEGF的含量也低于F组 ,(P <0 0 5 )。②F组中膜平滑肌细胞明显增生、胶原纤维较N组增多 ,S组较F组则减轻。③免疫组化、原位杂交显示F组大鼠肺细小动脉VEGF及其mRNA与N组比较增加 (P <0 0 1) ,而S组与F组比较 ,则降低 (P <0 0 5 ,P <0 0 1)。结论　VEGF参与了慢性低氧性肺动脉高压的形成 ,苏拉明通过抑制VEGF的作用而有效地降低低氧所致的肺动脉高压。

Effects of suramin on vascular endothelial growth factor of chronic hypoxia and hypercapnia rats

AIM To explore the roles of vascular endothelial growth factor (VEGF) in hypoxia pulmonary hypertension and effects of suramin. METHODS Thirty SD rats were randomly divided into normal control group (N), hypoxia hypercapnia group(F), hypoxia hypercapnia +suramin group (S). The levels of VEGF in serum and in lung tissue were measured by ELISA, the ultrastructure of pulmonary arterioles was observed by electron microscopy, the expression of VEGF was observed by immunohistochemistry, the expression of VEGFmRNA was observed by in situ hybirdization. RESULTS ①Mean pulmonary arterial pressure(mPAP), weight ratio of RV to LV+S, the leves of VEGF in serum and in lung tissue of group F were significantly higher than that of group N and group S (P<0.01,P<0.05).②Electron microscopy showed proliferation of smooth muscle cells and collagenous fibers of pulmonary arterioles in rats of group F, and suramin reversed the changes mentioned above.③VEGF and VEGFmRNA in pulmonary arterioles were significantly higher in rats of group F than that of group N(P<0.01), they were significantly decreased in rats of group S than that of group F. CONCLUSION VEGF plays an important role in the process of hypoxia pulmonary hypertension, and suramin can prevent hypoxia pulmonary hypertension by inhibiting the role of VEGF.-