Figure 1. Stress levels following immobilization stress. For stressed rats, ACTH levels were 2657.5 ± 668.64 pg/mL at 30 min, 2404.54 ± 679.74 pg/mL at 60 min, and 1306.66 ± 453.46 pg/mL at 180 min (N = 4; error bars = SD). Non-stressed rats had ACTH levels of 775.833 ± 121.12 pg/mL. There were significant differences in the ACTH levels of non-stressed rats and rats that experienced 30, 60, or 180 min of acute immobilization stress (p < 0.05).