Effect of aspirin on vascular tone and reactivity to vasoactive amines in the dog lung.

The effect of increasing blood levels of aspirin on pulmonary hemodynamics and pressor response to vasoactive amines was examined in the isolated canine lung lobe, blood perfused at constant flow. At steady state lobar vascular resistance (LVR), lobes were challenged with either 250 μg serotonin (5-HT; n=4), 5.0 μmol acetylcholine (ACh; n=4) or 50 μg norepinephrine (NE; n=4) before and after blood aspirin concentration [ASA] was incrementally increased from 17 to 3140 μM