Lung Uptake and Antianaphylactic Effects of KWD 2131 (A β‐Adrenergic Agonist) in Perfused Guinea‐Pig Lungs

: The lung uptake and modulating effects of KWD 2131 [1(3,5-dihydroxyphenyl)-2-(1,1-dimethyl-2-hydroxyethyl) amino ethanol], a β-adrenergic agonist, on pulmonary perfusion flow and histamine release from anaphylactic guinea-pig lungs were studied using an isolated perfused lung model. The lung extraction ratio, as calculated from the concentration of drug in the inflowing and outflowing medium in single pass studies was <0.05 at steady state which was achieved within 3 min. after start of drug infusion. Statistically significant protection to antigen elicited reduction in perfusion flow and inhibition of histamine release were obtained at the inflowing concentration 1.5 × 10−6 mol/l but not at 1.5 × 10−7 mol/l. The observed inhibition of the anaphylactic decrease in the perfusion flow can partly be explained by the decreased histamine release.