Leukocyte and lymphocyte subsets after a short pharmacological stress by intravenous epinephrine and hydrocortisone in healthy humans.

Nine healthy volunteers received epinephrine and hydrocortisone intravenously in order to assess the typical acute response to a brief stress, of leukocyte and lymphocyte subsets, acute phase reactants and lymphocyte reactivity to T and B mitogens. At 10 min., all leukocyte subsets were increased, especially mononuclear cells. At 1 hour, moderate lymphopenia and monocytopenia occurred. At 6 hours, neutrophilia and eosinopenia were observed. During the lymphocytic early wave, all the lymphocyte subset counts increased, particularly T-suppressive/cytotoxic and natural killer cells. As a consequence, the percentage of T cells decreased and the CD4/CD8 ratio fell. No changes in acute phase reactants occurred over the 24 hours of the study. All leukocyte and lymphocyte subsets were normalized and mitogen reactivity was unchanged 24 hours after the stress. These typical shifts in leukocyte subsets could probe the adrenocortical and medullary response to an environmental stressor.