Fig. 4.
Effects of inhibition of late sodium current (INaL) in mice with altered sodium channel function. A and B: ECGs recorded in S571E male mice at 4 mo with low heart rate (low HR; A) and high heart rate (high HR; B) before (baseline) and following inhibition of INaL with GS967. C: data for average RR interval duration, standard deviation of RR intervals (SDRR), and low frequency-to-high frequency (LF/HF) ratio in in young S571E mice with low HR (n = 16) and young S571E mice with high HR (n = 16) before (base) and after inhibition of INaL with GS967 (GS). Data are presented as medians and interquartile ranges. *P < 0.05 vs. baseline; †P < 0.05 vs. low HR under the same experimental condition.