Figure 1.

MeCP2 deficient mice display severe autonomic dysfunction. (A) Representative 2 s ECG tracings from 10 week-old male wild-type and NULL (male Mecp2^TM1.1Bird/Y) mouse. Below the tracing is a 15 s instantaneous heart rate graph showing the irregular heart rate in the NULL mouse. (A’) Representative 2 s ECG tracing of a 9 month-old female WT mouse and NULL/+ (female Mecp2^TM1.1Bird/+) mouse showing the irregular heart rhythm and variable heart rate. (B and B’) The mean heart rate from telemetry recordings was binned into light and dark cycle and compared to age matched controls. (C and C’) Sudden bradycardic events defined as a heart rate below 200 bpm were quantified over a 24-h period in both male and female mice and compared to controls. (D-E and D’-E’) Heart rate irregularity was measured by the mean standard deviation of the RR interval (SDNN) and the coefficient of variation. (F-G and F’-G’) Temperature and activity levels were binned to light and dark cycles in both male and female mice and compared to controls. Data presented as mean ± SEM male n = 5–7 per genotype, female n = 8–10 per genotype *P < 0.05 **P < 0.01 ***P < 0.01.