Kubo K, Kobayashi T, Kusama S, Sakai A, Ueda G
Jpn Circ J. 1985 Jul;49(7):685-91. doi: 10.1253/jcj.49.685.
The effects of prostacyclin (PGI2) on alveolar hypoxic pulmonary vasoconstriction were investigated in the conscious adult sheep. In our model, hypoxia also produced increases in pulmonary arterial pressure (PPA) and pulmonary vascular resistance (PVR), indicating pulmonary vasoconstriction. PGI2 was injected rapidly as a 0.5 microgram/kg bolus via the right atrium in five sheep during normoxia and hypoxia. During normoxia, PGI2 increased PPA and cardiac output, and decreased systemic arterial pressure (PSA), systemic vascular resistance (SVR) and PVR. Left atrial pressure did not change. During hypoxia following PGI2 administration, PPA decreased, CO increased, and PVR decreased, suggesting dilator action on the pulmonary resistance vessels. As the same time PSA and SVR decreased, suggesting dilator action on the systemic resistance vessels. However, the degree of the decline in PVR caused by PGI2 was much greater during hypoxia than during normoxia. The decreases in PSA and SVR induced by PGI2 were not significant between hypoxia and normoxia. These findings confirm that PGI2 decreases pulmonary and systemic vascular resistances in normoxic and hypoxic sheep. Moreover, during hypoxia, associated with the increased PPA and PVR, the administration of PGI2 appears to be particularly effective in "normalizing" these parameters.
在清醒成年绵羊中研究了前列环素（PGI2）对肺泡低氧性肺血管收缩的影响。在我们的模型中，低氧也会导致肺动脉压（PPA）和肺血管阻力（PVR）升高，表明存在肺血管收缩。在五只绵羊处于常氧和低氧状态时，通过右心房快速注射0.5微克/千克的PGI2推注。在常氧状态下，PGI2使PPA和心输出量增加，而使体动脉压（PSA）、体循环血管阻力（SVR）和PVR降低。左心房压力未发生变化。在给予PGI2后的低氧状态下，PPA降低，心输出量（CO）增加，PVR降低，提示对肺阻力血管有扩张作用。与此同时，PSA和SVR降低，提示对体循环阻力血管有扩张作用。然而，PGI2导致的PVR下降程度在低氧状态下比在常氧状态下大得多。PGI2引起的PSA和SVR下降在低氧和常氧状态之间无显著差异。这些发现证实，PGI2可降低常氧和低氧绵羊的肺血管和体循环血管阻力。此外，在低氧状态下，与PPA和PVR升高相关，给予PGI2似乎在“使”这些参数“正常化”方面特别有效。
