Role of p38 Mitogen-Activated Protein Kinase in Neointimal Hyperplasia After Vascular Injury

Abstract —p38 mitogen-activated protein kinase (MAPK) is involved in intracellular signals that regulate a variety of cellular responses during inflammation. However, the role of p38 MAPK in atherosclerosis, a chronic inflammatory disorder, remains uncertain. The aim of the present study was to examine the role of p38 MAPK in the development of neointimal hyperplasia in balloon-injured rat carotid arteries. Immunohistochemical studies indicated that p38 MAPK was rapidly activated in the majority of medial cells in injured arterial walls. Rats treated with FR167653, a selective inhibitor of p38 MAPK, at a dosage of 10 mg · kg –1 · d –1 , had a 29.4% lower intima-to-media ratio than the untreated controls at 14 days after balloon injury ( P P