Effects of physical exercise on ADHD-like behavior in male and female adolescent spontaneously hypertensive rats.

The present study examined the effects of exercising (voluntary wheel running) during adolescence on attentional function in male and female spontaneously hypertensive rats (SHRs), a commonly used animal model of attention-deficit/hyperactivity disorder (ADHD). Once rats reached adulthood, they received one session in which a light was presented 12 times but not reinforced, followed by training sessions in which the light was paired with a food reward. Male and female SHRs that had access to running wheels exhibited levels of unconditioned orienting behavior that were similar to Wistar-Kyoto rats (normo-active control) while SHRs that did not have access to running wheels exhibited higher levels of unconditioned orienting behavior. When the light was later paired with food there were no differences between the groups of male rats, but exercising female SHRs exhibited a decrease in conditioned food cup behavior. Consistent with their established phenotype, SHR rats exhibited more locomotor activity during an open field exploration session than WKY rats, but there was no relationship between orienting behavior and locomotor activity. Together these data suggest that physical exercise during adolescence can benefit attentional capabilities.