Role of Tyrosine Phosphorylation in U46619-induced Vasoconstriction of Pulmonary Vasculature and Its Modulation by Genistein, Daidzein, and Equol

We compared the effects of genistein with its structural derivatives daidzein and equol on excitation of pulmonary artery and vein. The concentration of genistein necessary to inhibit contractions evoked by U46619 (1nM-100 microM) ranged from 10 to 100 microM. Genistein (55 microM) reduced KCl-responses by approximately 50% and essentially abolished those evoked by U46619. Daidzein was much less effective against either agonist, and equol was …