Figure 3. Ouabain–digoxin antagonism in de‐endothelialized arteries and arteries treated with prazosin or PP2 .

A, digoxin (0.3 nm) antagonizes the increase in myogenic constriction (MT₇₀) induced by 0.1 nm ouabain in a de‐endothelialized mesenteric small artery. B, digoxin (10 nm) antagonizes the increase in myogenic constriction (MT₇₀) induced by 3 nm ouabain in a mesenteric small artery treated with α1‐adrenoceptor blocker prazosin (100 nm). C, digoxin (10 nm) antagonizes the increase in myogenic constriction (MT₇₀) induced by 3 nm ouabain in a mesenteric small artery treated with the c‐Src‐kinase inhibitor PP2 (1 μm). D, summarized data on the antagonism of ouabain‐induced increases in MT₇₀ in de‐endothelialized arteries, and in arteries treated with 100 nm prazosin or 1 μm PP2; n = 5 arteries in each case. Endothelium removal or treatment with prazosin or PP2 did not significantly affect the antagonism of the ouabain‐induced increase in MT₇₀ by digoxin (P > 0.05 in all cases).