Figure 4.

Amphetamine increases the temperature at exhaustion. Rats received (i.p.) either saline or Amp (1 or 2 mg/kg). Five min later they were placed on a treadmill in a warm environment (32°C) and run at 18 m/min at a 5° incline. For rats running at this constant workload in the heat, low dose amphetamin (1 mg/kg) increased time to exhaustion (A), and temperature at exhaustion (B); Amp at higher dose (2 mg/kg) increased only the temperature at exhaustion (B). Horizontal bars represent group means ± SEM, n = 8 for each group.