Differences in the Effects of Inhalation of Sulfur Dioxide and Cigarette Smoke

In the anesthetized dog the inhalation of sulfur dioxide caused bronchoconstriction which persisted even after acute and chronic denervation, The basic mchanisms responsible for this bronchoconstriction as well as the accompanying bronchial arterial vasodilatation are different from those activated during the inhalation of cigarette smoke.