The percentage of dopamine neuron destruction in lesioned hemispheres of the MSR (n = 10), NSR (n = 9), MSNR (n = 10) and NSNR (n = 10) rats. A two-way ANOVA revealed main effects of stress (F(1,35) = 12.1, p < 0.01) and exercise (F(1,35) = 347.8, p < 0.0001) and a significant interaction between stress and exercise (F(1,35) = 8.8, p < 0.01).*(MSR vs MSNR, p < 0.001, and NSR vs NSNR, p < 0.001, post-hoc Tukey HSD test).