Voluntary exercise does not enhance long-term potentiation in the adolescent female dentate gyrus

The hippocampus is a dynamic brain structure involved with learning and memory. Long-term potentiation (LTP) is a neuronal model of learning and memory and, in adult rodents, is enhanced by voluntary exercise (VEx). The current study sought to elucidate whether synaptic plasticity in the male and female adolescent hippocampus is augmented by VEx. Consistent with previous studies, VEx significantly enhanced LTP in adolescent males following weak and strong theta-burst stimulation. Despite running the same amount as males, however, VEx did not enhance LTP in females above non-runner females. Surprisingly, the exercise-induced enhancement to LTP in males was seen in the absence of a change in brain derived neurotrophic factor in the dentate gyrus (DG). These findings indicate that adolescent males and females are differentially sensitive to the potentiating effect of exercise on hippocampal synaptic plasticity.