Rapid Cellular Genesis and Apoptosis: Effects of Exercise in the Adult Rat

Long-term aerobic exercise improves cognition in both human and nonhuman animals and induces plastic changes in the central nervous system (CNS), including neurogenesis and angiogenesis. However, the early and immediate effects of exercise on the CNS have not been adequately explored. There is some evidence to suggest that exercise is initially challenging to the nervous system and that the plastic changes commonly associated with chronic exercise may result as adaptations to this challenge. The current experiment assessed levels of apoptosis, angiogenesis, and neurogenesis during the first week of an exercise regimen in the adult rat. The results indicate that exercise rapidly induces these processes in the hippocampus and cerebellum. The temporal pattern of these events suggests that voluntary exercise in the adult rat rapidly and transiently induces apoptosis, followed by angiogenesis. Neurogenesis is an immediate and independent consequence of exercise in the hippocampus that may require the additional metabolic support supplied by angiogenesis. This is the first report of CNS neuronal apoptosis as a consequence of exercise in the adult rat and suggests that this process is a potential mediator of rapid exercise-induced plasticity.