Figure 5.
Effect of cystamine (CYS) on calcium and tension in rat mesenteric arteries contracted with phenylephrine. (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 10 μM phenylephrine (Phe), followed by addition of increasing concentrations of cystamine. Cystamine 100 μM caused acute reduction in active tension and F340/F380. This inhibition persisted for about 10 min after which an increase in F340/F380 was observed together with a rise in tension. (B) Average changes in Fura‐2 ratio and tension. *P < 0.05 versus initial response.