Contribution of p38 MAPK to the Ameliorating Effect of Enriched Environment on the Cognitive Deficits Induced by Chronic Cerebral Hypoperfusion.

BACKGROUND/AIMS An enriched environment (EE) ameliorates learning and memory impairments induced by chronic cerebral hypoperfusion, and the p38 mitogen-activated protein kinase (p38 MAPK) signaling pathway exerts both beneficial and deleterious effects on the nervous system during the progression of ischemia. METHODS The present study investigated whether p38 MAPK participates in the process by which EE exposure ameliorates the cognitive deficits induced by chronic cerebral hypoperfusion. RESULTS EE exposure significantly enhanced the cognitive performance of vascular dementia (VD) model rats, and p38 MAPK protein decreased in parallel with cognitive improvements. Inhibition of p38 MAPK function by its selective inhibitor SB203580 improved the cognition index of VD rats and upregulated p38 MAPK expression with p38 MAPK antisense oligodeoxynucleotides. This impaired cognition in VD rats could not be rescued by EE exposure. CONCLUSION p38 MAPK participates in the process by which EE exposure ameliorates cognitive deficits induced by chronic cerebral hypoperfusion.