Potent vasoconstriction by tyramine but no significant constriction by nicotine in isolated dog ear arteries

Using the cannula inserted method, vascular effects of nicotine were investigated in isolated, perfused dog intermediate auricular arteries, comparing with those of norepinephrine and tyramine. Norepinephrine and tyramine produced strong vasoconstrictions in a dose-related manner, but nicotine did not induce any significant vasoconstriction.