Activation of GPER decreased the increase in INaLand peak INa induced by ISO but did not affect INa kinetics
To establish whether GPER will restore the effects of ISO on hiPSC-CMs, we characterized sodium channel function under G1 and G15 treatment. We observed that G1 pretreatment eliminated the increase inI NaL and peak I Na induced by ISO which was similar to E2. Notably, the effects of E2 were abolished by G15 pretreatment (Figure 6A-E). Activation or inhibition of GPER did not affect the V1/2 and k values of activation and inactivation in hiPSC-CMs treated with ISO as described before (Figure 6F and H-K). G1 or G15 pretreatment had no effects on the τ value of recovery from inactivation caused by ISO (Figure 6G and L; Supplemental Figure 3B). The data of Mean ± S.E.M are found in supplementary material online, Supplemental Table 1-7.