Effects of 8-Isoprostaglandin E 1 on the Systemic and Pulmonary Circulations in Dogs 1

Abstract

Summary

The effects of 8-iso-prostaglandin E₁ on the systemic and pulmonary circulations were studied and compared with those of PGE₁ and PGF_2α in anesthetized dogs. It was found that the iv administration of 8-iso-PGE₁ decreased systemic arterial pressure slightly and increased heart rate and myocardial contractile force slightly. The magnitude of the systemic hypotensive effect of 8-iso-PGE₁ was equivalent to approximately 1/125 to 1/250 of that of PGE₁ in dogs. On the other hand, the pulmonary hypertensive action of 8-iso-PGE₁ was 5 times greater than that of PGE₁. The present study indicates that 8-iso-PGE₁ increases pulmonary arterial pressure through its vasoconstrictor action on the pulmonary vascular bed.