Cassin S, Winikor I, Tod M, Philips J, Frisinger J, Jordan J, Gibbs C
Pediatr Pharmacol (New York). 1981;1(3):197-207.
The effects of prostacyclin (PGI2) and its metabolite, 6-keto-PGF1 alpha, on pulmonary and systemic circulations of anesthetized, unventilated fetal goats and sheep were evaluated in situ using an isolated perfused lower left lobe preparation. Results from infusions of PGI2 into the left pulmonary artery suggested dose-dependent decreases in pulmonary vascular resistance (PVR) and mean systemic arterial pressure (SAP). Two-minute infusions produced more pronounced reductions in PVR than 1-minute infusions, and fetal goats exhibited greater depressor responses to PGI2 (2-minute infusions) than fetal lambs. For every 10% decrease in mean pulmonary arterial pressure (PAP), SAP decreased by 3% in sheep receiving 1-minute infusions of PGI2. Systemic hypotensive responses and increases in heart rate were similar in both species. PGI2 appears to be a more powerful dilator of the fetal pulmonary circulation than PGE1 or PGE2; also, intrapulmonary infusions of PGI2 resulted in greater and more sustained systemic hypotensive effects than similar infusions of PGE1 and PGE2. The stable metabolite of PGI2, 6-keto-PGF1 alpha, produced attenuated pulmonary vasodilation. Since PGI2 may produce systemic hypotension, the use of this agent in treatment of persistent pulmonary hypertension should be considered with caution.
使用离体灌注左下叶制备方法，在原位评估了前列环素（PGI2）及其代谢产物6-酮-前列腺素F1α对麻醉、未通气的胎羊和胎山羊肺循环和体循环的影响。将PGI2注入左肺动脉的结果表明，肺血管阻力（PVR）和平均体动脉压（SAP）呈剂量依赖性降低。2分钟输注比1分钟输注使PVR产生更明显的降低，并且胎山羊对PGI2（2分钟输注）的降压反应比胎羊更大。在接受1分钟PGI2输注的绵羊中，平均肺动脉压（PAP）每降低10%，SAP降低3%。两种动物的全身降压反应和心率增加相似。PGI2似乎是比PGE1或PGE2更强有力的胎儿肺循环扩张剂；此外，与PGE1和PGE2的类似输注相比，肺内输注PGI2产生更大且更持久的全身降压作用。PGI2的稳定代谢产物6-酮-前列腺素F1α产生减弱的肺血管舒张作用。由于PGI2可能产生全身低血压，因此在治疗持续性肺动脉高压时应谨慎考虑使用该药物。
