Fig. 2.

Role of vascular smooth muscle cell (VSMC) Na⁺-K⁺-ATPase in K⁺-induced vasodilation. A: vasodilation to increases in [K⁺]_o was inhibited by treatment with ouabain (10⁻⁴ M, n = 14). B: BaCl₂ [3 × 10⁻⁵ M, P = not significant (NS)] had no effect on the vasodilation to K⁺ (n = 5). C: BaCl₂ reduced the vasodilation only in the case where Na⁺-K⁺-ATPase activity was inhibited (n = 5). D: endothelial denudation had no inhibitory effect on the vasodilation (n = 9). E: vasodilation to K⁺ was abolished by treatment with ouabain alone (10⁻⁴ M) in endothelial cell (EC)-denuded vessels (n = 5). Values are means ± SE. *P < 0.05 vs. control (A and E) or ouabain alone (C).