L-精氨酸和硝普钠对缺氧大鼠肺动脉压及血管结构变化的影响

Effect of L-arg and SNP on Pulmonary Arterial Pressure and Vascular Structural Changes of Chronically Hypoxic Rats

观察一氧化氮合成的前体物质L-精氨酸和一氧化氮供应剂硝普钠对慢性缺氧大鼠肺动脉压、肺泡内无肌性血管肌化程度以及肺泡内和肺外动脉内皮和平滑肌细胞超微结构的影响，探讨外源性一氧化氮在限制缺氧性肺动脉高压形成和发展中的作用机制。结果发现：L-精氨酸和硝普钠均可使慢性缺氧大鼠的肺动脉压显著降低，肺泡内无肌性血管肌化程度明显减轻，并且可保护肺血管防止缺氧引起的内皮损伤和中膜平滑肌细胞表型的改变。提示给缺氧大鼠提供充足的外源性一氧化氮或一氧化氮合成的前体物质，可以保护内皮并防止缺氧引起的肺血管功能障碍和结构损伤，从而限制缺氧性肺动脉高压的发生和发展。

The effects of L-arginine (L-arg) and sodium nitroprusside (SNP) on pulmonary arteri-al pressure, the percentage of muscularization of intra-acinar vessels and ultrastructural changes of extra pulmonary artery and pulmonary arteriole of chronically hypoxic rats were studied. The results showed that: (1) Both L-arg and SNP decreased rnean pulmonary arte-rial pressure of chronlcally hypoxic rats slgnificantly. (2) Both L-arg and SNP reduced the percentage of muscularization of intra-acinar vessels of chronically hypoxic rats significantly. (3) Both L-arg and SNP protected pulmonary artery from the damages of endotheluium and the changes in smooth muscle cell phenotype by hypoxla. These results suggested that ex-ogenous nitric oxide might play a role in the protection of pulmonary arterlal function and structure which alleviate the development of pulmonary hypertenslon induced by chronic hy-poxia.