['RANTES plays an important role in the production of allergic inflammation of the airway through its chemotactic activity for eosinophils. However, the intracellular signal regulating RANTES expression in human pulmonary vascular endothelial cells has not been determined. In the present study, therefore, we examined the role of p38 mitogen-activated protein (MAP) kinase in RANTES production by tumor necrosis factor (TNF)-alpha-stimulated pulmonary vascular endothelial cells in order to clarify the signal transduction pathway regulating RANTES production by pulmonary vascular endothelial cells.', 'We examined p38 MAP kinase activation, and the effect of SB 203580, as the specific inhibitor for p38 MAP kinase, on p38 MAP kinase activity and RANTES production by TNF-alpha-stimulated human pulmonary vascular endothelial cells.', 'The results showed that TNF-alpha induced RANTES production and p38 MAP kinase activity in human pulmonary vascular endothelial cells. Abrogation of p38 MAP kinase activity by SB 203580 repressed TNF-alpha-induced p38 MAP kinase activity and RANTES production.'] Does p38 MAP kinase regulate RANTES production by TNF-alpha-stimulated human pulmonary vascular endothelial cells?