Figure 6.
Effect of cystamine (CYS) on calcium and tension in rat mesenteric arteries contracted with high extracellular potassium. (A) Original traces of Fura‐2AM ratio (ΔF340/F380) as a measure of change in [Ca2 +]i and tension of rat mesenteric small artery in response to high extracellular potassium (KPSS) applied in combination with 1 μM phentolamine, to minimize stimulated release of neuronal noradrenaline. Once KPSS contraction was stable, increasing concentrations of cystamine were added. Active tension was reduced following the addition of cystamine 100 μM, but with no change in F340/F380 ratio. (B) Average changes in Fura‐2 ratio and tension. *P < 0.05 versus initial response.