Figure 5. Manipulations of RyR2, and NCX and its efficacy on spontaneous contraction in hiPS-CMs.
A: K201 (2 μM), a selective RyR2 stabilizer gradually decreased the frequency of spontaneous contraction in a cluster of hiPS-CMs and eventually terminated spontaneous contraction (n=5/5). HiPS-CMs remained excitable by electrical stimulation. After 2 min of K201 exposure, a ~2-fold decrease in frequency of automaticity was statistically significant (right panel)
B: Similar effects of 5μM tetracaine infusion on spontaneous contraction in hiPS-CMs
C: SEA0400 (2 μM), an inhibitor of the forward mode of NCX suppressed spontaneous contractions in a cluster of iPS-CMs; an effect that was reversible by washing out SEA0400 (right trace) (n=4/4).