腺苷对慢性低氧高二氧化碳大鼠肺动脉高压的影响

目的　观察腺苷对慢性低氧高二氧化碳大鼠血流动力学的影响及氨茶碱的拮抗作用。方法　从大鼠肺动脉内注入腺苷溶液。氨茶碱组大鼠预先注入氨茶碱进行处理。结果　 2 5 μg·kg-1·min-1组 (T组 ) ,5 0 μg·kg-1·min-1组 (F组) ,10 0 μg·kg-1·min-1组 (H组 )用药后平均肺动脉压(mPAP)分别降低 18 5 %± 9 9% ,2 7 1%± 4 5 % ,37 2 %± 7 2 % ,明显低于用药前 (P均 <0 0 1) ,而NO水平则明显升高 (P <0 0 5 ,P <0 0 1,P <0 0 1)。T组 ,F组用药后mPAP/mSAP(平均体循环压 )明显低于用药前 (P <0 0 1,P<0 0 5 ) ,H组差异无显著性 (P >0 0 5 )。氨茶碱组用药后mPAP与F组比较差异有显著性 (P <0 0 1)。结论　腺苷剂量依赖性降低慢性低氧高二氧化碳大鼠的肺动脉高压 ,其机制可能部分依赖于内皮细胞NO的释放。小剂量腺苷对肺循环具有良好选择性。氨茶碱能拮抗腺苷舒张肺血管的作用。

Effects of adenosine on pulmonary hypertension of chronic hypoxia and hypercapnia rats

AIM To evaluate the effects of adenosine on hemodymics induced by chronic hypoxia and hypercapnia rats and the influence of aminophylline METHODS Adenosine or an equal volume saline was infused into the pulmonary artery in differents doses Aminophylline group was treated by aminophylline before the infusion of adenosine RESULTS In rats with pulmonary hypertension, adenosine caused a significant decrease in mPAP in dose of 25, 50, 100 μg·kg -1 ·min -1 (P<0 01) and a significant increase in levels of NO(P<0 05, P<0 01, P<0 01), with a decrease in mPAP/mSAP in dose of 25, 50 μg·kg -1 ·min -1 (P<0 01, P<0 05) The pulmonary vascular effects of adenosine in rats attenuated by prior treatment of aminophylline CONCLUSION Adenosine may decrease the mPAP of rats with pulmonary hypertension Infusion of adenosine into the pulmonary circulation cause selective pulmonary vasodilation in smaller doses The mechanism may partly depend on the release of NO from the endothelium cells Aminophylline can attenuate the relaxation of adenosine