The intratracheal injection of one moderate dose of adrenalin in rabbits whose vagi are divided produces a marked pulmonary edema in a large percentage of cases. The same dose in normal animals causes only slight effects.
Artificial respiration greatly reduces the production of pulmonary edema in vagotomized rabbits after adrenalin.
As adrenalin can exert a bronchoconstrictor effect, evidence is submitted to show that the aspirating action of the lung alveoli under this condition apparently plays an important part in the production of adrenalin pulmonary edema. On the basis of this mechanism the protective action of artificial respiration is explained.
Stenosis of the trachea facilitates. the production of adrenalin pulmonary edema in rabbits whose vagi are intact.
The intratracheal injection of adrenalin in vagotomized rabbits produces a temporary incoordination between the heart ventricles, visible on inspection, so that the left ventricle beats apparently half as fast as the right, causing hyperemia of the lungs and hemorrhages.
Atropine injected intratracheally in vagotomized rabbits exerts a protective action against adrenalin pulmonary edema.