HIGH-INTENSITY PHYSICAL EXERCISE DISRUPTS IMPLICIT MEMORY IN MICE INVOLVEMENT OF THE STRIATAL GLUTATHIONE ANTIOXIDANT SYSTEM AND INTRACELLULAR SIGNALING

Physical exercise is a widely accepted behavioral strategy to enhance overall health, including mental function However, there is controversial evidence showing brain mitochondrial dysfunction, oxidative damage and decreased neurotrophin levels after high intensity exercise, which presumably worsens cognitive performance Here we investigated learning and memory performance dependent on different brain regions, glutathione antioxidant system, and extracellular signal-regulated protein kinase 1/2 (ERK1/2), serine/threonine protein kinase (AKT), cAMP response element binding (CREB) and dopamine and cyclic AMP-regulated phosphoprotein (DARPP)-32 signaling in adult Swiss mice submitted to 9 weeks of high intensity exercise The exercise did not alter the animals' performance in the reference and working memory versions of the water maze task On the other hand, we observed a significant impairment in the procedural memory (an implicit memory that depends on basal ganglia) accompanied by a reduced antioxidant capacity and ERK1/2 and CREB signaling in this region In addition, we found increased striatal DARPP 32 Thr-75 phosphorylation in trained mice These findings indicate an increased vulnerability of the striatum to high intensity exercise associated with the disruption of implicit memory in mice and accompanied by alteration of signaling proteins involved in the plasticity of this brain structure (C) 2010 IBRO Published by Elsevier Ltd All rights reserved