目的 :在内毒素休克发病早期 ,肺动脉压增高而平均动脉压降低。我们发现此时肺动脉肌层有过氧亚硝基阴离子 (ＯＮＯＯ- )生成 ;外源性ＯＮＯＯ- 可导致离体肺动脉反应性异常 ,促进肺动脉压增高。有研究报道 ,ＯＮＯＯ- 可直接引起血管舒张。但ＯＮＯＯ- 对肺动脉的舒张特性迄今 OBJECTIVE: In the early stage of endotoxic shock, pulmonary arterial pressure increases and mean arterial pressure decreases. We found that at this time the pulmonary artery myositis peroxynitrite (ONOO-) generation; exogenous ONOO- can lead to abnormal pulmonary artery reactivity in vitro and promote pulmonary hypertension. Some studies have reported that ONOO- can directly cause vasodilation. But ONOO- on the pulmonary artery relaxation characteristics so far