Fig. 2.

Effect of leptin withdrawal on 24-h energy expenditure. Energy expenditure and locomotor activity was monitored on days 6–8 in leptin-treated mice (Lep), days 1–7 after leptin withdrawal in leptin-FF (FF1–7) and leptin-NC (NC) mice, days 1–3 after leptin withdrawal in PBS controls, and for 72 consecutive hours in ob/ob mice (n = 4 per group for all groups). Because the PBS control mice, ob/ob mice, and leptin-NC mice showed little day-to-day variability in energy expenditure and activity, all data were averaged and reported as a single value. The data for leptin-FF mice vary over time and are thus reported at 24-h intervals. (A) Energy expenditure. (B) Locomotor activity (*, P < 0.01 vs. PBS; †, P < 0.05 vs. FF at every time point).