高原鼠兔肺动脉压与NO的变化

目的 :研究慢性缺氧环境下NO及NOS在肺循环适应机制中的作用 ;方法 :Wistar大鼠从 2 2 6 0m带到 3780m的高原饲养 30天后进行肺动脉压及血液学、组织学观察 ,并和当地的适应动物高原鼠兔进行比较 ;结果 :缺氧 30天的大鼠血清NO的水平及NOS的活性均低于高原鼠兔 ,两者分别为 5 5 .40 μmol/L± 3.76 μmol/L、87.49μmol/L±5 .74μmol/L,和 1 .33u/ml± 0 .1 2u/ml、1 .99u/ml± 0 .1 3u/ml,肺动脉压增高 ,左右心室比重高原鼠兔为 0 .2 3,而Wis tar大鼠为 0 .47;高原鼠兔的肺动脉壁非常薄 ,而且没有平滑肌层 ,而大鼠同样大小的肺动脉在内外层的弹力纤维中间有一较厚的平滑肌层 ,肺动脉中层的厚度 ,鼠兔为 9.3% ,大鼠为 2 8.4% ,肺动脉增厚程度与NO的水平呈负相关 ;结论 :低氧环境下NO及NOS的代谢异常 ,既导致了大鼠的缺氧性肺血管收缩反应 ,又参与了肺血管的结构改建过程 ,高原鼠兔无低氧性肺血管收缩 ,NO在维持其张力方面起到了一重要作用。

CHANGES ON PULMONARY ARTERIAL PRESSURE AND LEVEL OF NO IN PIKA

To study the effects of chronic hypoxia on NO and NOS in pulmonary circulation under high altitude condition.Method:14 Wistar rats,they were migrated to 3 780m altitude for 30 days from 2 260m,were used in this study.The pulmonary arterial pressure,level of NO and NOS in lung blood and other aspect of histology were invastigated after 30 days altitude and conpared with those data with Pika.Results:Level of NO and NOS in rats were lower than that in Pika.Pulmonary hypertension,large right/left ventricum(0.47) in Wister rats could be found and the pulmonary arteriole wall was thicker so that there is a thick smooth sandwiched between inner and out elastic lamina,but contrary in Pika.There was a positive relation between thicker pulmonary arteriole wall and discreased NO.Conclusion:The abnormal changes of No and NOS under hypoxic environment could induce lung vascular contraction and associated with the changes of lung vascular construction.