Fig. 8.

Effects of intravenous injection of 3 mg/kg hexamethonium on arterial diameter (representative original recording; A) and mean arterial tone (B) and on cytosolic Ca²⁺ concentration ([Ca²⁺]_CYT) representative original data (C) and mean data (D) in exposed femoral arteries of control (Ctrl) and smooth muscle-specific Na⁺/Ca²⁺ exchanger-1 transgenic (TG) mice in vivo. [Ca²⁺]_i, intracellular Ca²⁺ concentration. Hexamethonium redued [Ca²⁺]_CYT to ≪50 nM and virtually abolished tone in both Ctrl and TG arteries. Ctrl passive diameter (PD) = 382 ± 14 μm (n = 8); TG PD = 386 ± 12 μm (n = 8). Values are means ± SE. Statistics were by two-way ANOVA. *P < 0.05 and ***P < 0.001 vs. basal Ctrl mice; ###P < 0.001 vs. basal TG mice. Numbers of mice are in parentheses.