Dopamine effect on bronchomotor tone in vivo.

The effect of increasing doses of dopamine (inhaled or infused) on pulmonary resistance (RL) was measured in 4 normal and in 4 asthmatic subjects. Dopamine, in doses sufficient to raise systolic blood pressure 25 mmHg, did not change RL. However, dopamine, inhaled and infused, significantly decreased histamine-induced bronchoconstriction both in normal and in asthmatic subjects. Thus, we conclude that if dopamine is released by the adrenal medulla during an asthmatic attack, it should have a beneficial rather than a deleterious effect.