Active Constriction of Small Pulmonary Arteries in Rabbit

This communication deals with the demonstration of active pulmonary vasomotion by injecting plastic material (vinyl acetate) which forms casts of the small pulmonary arteries simultaneously on a control side and on the test side submitted to action of vasoconstrictor drugs. Comparisons were made by direct microscopic observations and by weighing the casts after the lung tissue had been digested. Other indices such as relative weight of the two lungs, relative denseness of vascularity and estimates of pulmonary resistance supplied supplementary evidence of pulmonary vasomotion.