Accordingly, in the current study, phosphorylation (activation) of intracellular p38 MAPK in peripheral blood lymphocytes was analyzed by flow cytometry every 2 h for 12 h following the initial injection of IFN-alpha in eleven patients with chronic hepatitis C. Hourly assessments of plasma concentrations of adrenocorticotropic hormone, cortisol and interleukin-6 were also obtained.