Estrogen suppressed the ISO-induced increase in peak
INa amplitude but did not alter INakinetics
Exposure of hiPSC-CMs to different concentrations of E2 (0.01 nmol/L, 1
nmol/L and 100 nmol/L, 1h) increased peak I Nadensity (Figure 3A-C), but did not affect the V1/2 andk values of activation and inactivation or τ value of recovery
from inactivation (Figure 3F-L, Supplemental Figure 2A). Treatment of
hiPSC-CMs with ISO resulted to an increase in peakI Na (Figure 1B and C, Figure 3A),and the effect was blunted by 1 nmol/L E2 (Figure 3A, D and E).
Interestingly, a significant difference was observed in peakI Na between 0.01 nmol/L E2 and 1 nmol/L E2 in
cells exposed to ISO indicating that the effects of E2 were
concentration dependent (Figure 3A, D and E). However, E2 at any
concentration did not rescue the increase of the V1/2values of activation and inactivation and the τ value of recovery from
inactivation induced by ISO (Figure 3M-S, Supplemental Figure 2B). Full
statistical details on Mean ± S.E.M and the number of cells are found in
supplementary material online, Supplemental Table 2-7.