PHYSICAL-ACTIVITY INCREASES MESSENGER-RNA FOR BRAIN-DERIVED NEUROTROPHIC FACTOR AND NERVE GROWTH-FACTOR IN RAT-BRAIN

Brain-derived neurotrophic factor (BDNF) and nerve growth factor (NGF) support the viability and function of many types of neurons, and are likely mediators of activity-dependent changes in the CNS. We examined BDNF and NGF mRNA levels in several brain areas of adult male rats fo llowing 0, 2, 4, or 7 nights with ad libitum access to running wheels. BDNF mRNA was significantly increased in several brain areas, most no tably in the hippocampus and caudal 1/3 of cerebral cortex following 2 , 4, and 7 nights with exercise. Significant elevations in BDNF mRNA w ere localized in Ammon's horn areas 1 (CA1) and 4 (CA4) of the hippoca mpus, and layers II-III of the caudal neocortex and retrosplenial cort ex. NGF mRNA was also significantly elevated in the hippocampus and ca udal 1/3 of the cortex, affecting primarily the dentate gyrus granular layer (DG) and CA4 of the hippocampus and layers II-III in caudal neo cortex.