Actions of Prostaglandins E 1 and F 2α on Isolated Intrapulmonary Vascular Smooth Muscle 1

Summary

The effects of PGE₁ and PGF_2α were studied on isolated strips of intrapulmonary arteries and veins from dog, sheep, swine and man. PGF_2α contracted human arterial strips in a dose-dependent fashion, relaxed slightly sheep arteries and had no effect on dog arteries. Canine, sheep and human venous strips were contracted by PGF_2α. PGE₁ relaxed slightly both veins and arteries from dog and sheep. Human arteries usually contracted slightly and human veins usually relaxed slightly to PGE₁. In a limited number of experiments, swine arteries and veins failed to respond to PGF_2α or PGE₁. All the vascular strips contracted well when exposed to NE. These results suggest that the responses of intrapulmonary vessels to PGF_2α and PGE₁ are species-dependent. PGF_2α generally exhibits a contractile action, especially on veins. PGE₁ usually relaxes intrapulmonary vessels. With regard to vessels from man, PGF_2α is a powerful stimulant while PGE₁ produces only small, variable effects.