Effect of histamine and propranolol on extravascular lung water

The ability of an intravenous infusion of 21 micrograms X kg-1 X min-1 histamine diphosphate to cause pulmonary edema was studied in dogs in which beta-blockade either was or was not in effect, since current evidence suggests that beta-blockade can prevent catecholamines from antagonizing the vascular permeability effect of histamine in the systemic circulation. Mixed venous histamine levels ranging from 140 to 580 ng/ml were achieved; norepinephrine and epinephrine levels increased significantly, although in animals receiving propranolol, heart rate remained depressed. Neither lung wet weight-to dry weight ratio nor extravascular lung water increased in animals receiving histamine or histamine and propranolol. We conclude that the inability of histamine to produce substantial pulmonary edema cannot be explained on the basis of catecholamine stimulation of beta-adrenergic receptors within the lung.