Prevention of Puerarin on Pulmonary Hypertension in Rats Induced by Chronic Hypoxia and Hypercapnia

Objective To study the effects of puerarin on pulmonary hypertension in rats induced by chronic hypoxia and hypercapnia.Methods Thirty Sprague-Dawley rats were randomly divided into normal control group(NC),hypoxic hypercapnia group(HH) and hypoxic hypercapnia+puerarin group(HP). Mean pulmonary aterial pressure(mPAP) and mean carotid arterial pressure(mCAP) were measured.MMP-2、MMP-9、TIMP-2 and their mRNA were observed in pulmonary arterioles by the technique of immunohistochemistry and in situ hybridization. Results ①mPAP was significantly higher in rats of HH group than that of NC group and it was much lower in rats of HP group than that of HH group(P0.01). Differences of mCAP were not significant in three groups;②Light microscopy showed media thickness of pulmonary arterioles was much higher in HH group than in NC group,and vessel cavity turned more straiter in HH group than in NC group.However,the damage of pulmonary arterioles in HP group was much slighter than that of HH group;③The levels of lung homogenates Hyr、MMP2 、MMP-9 and TIMP-2 were much higher in rats of HH group than those of NC group(P0.01),and lower in HP group than in HH group(P0.01);Plasma NO content of group HH was lower than that of group NC(P0.01),it was higher in group HP than that of group HH(P0.01);④Expression of MMP2、MMP-9、TIMP-2 and their mRNA in pulmonary arterioles were significantly higher in rats of HH group than those of NC group(P0.01),and they were lower in HP group than in HH group(P0.01).Conclusion Puerarin can improve pulmonary vessel remodeling by regulate MMPs/TIMPs system and inhibit the deposition of collagen in hypoxic hypercapnic rats.