Changes in Production of Cytokines by C57Bl/6J Mouse Spleen during Aggression Provoked by Social Stress

The effect of aggressive behavior shaped under social stress of various durations on the production of proinflammatory cytokines by splenic cells was examined on C57BL/6J mice. Aggressive mice were characterized by enhanced production of IL-2 and IFN-γ (released by T helper type 1 cells) and reduced secretion of TNF-α, whose major producers are monocytes and macrophages. Elevation of IL-2 and IFN-γ in aggressive mice resulted from enhancement of spontaneous and Con A-stimulated production, the most pronounced effect was demonstrated by the with a longer period (20 days) of victories. In contrast, spontaneous production of TNF-α was similar in control and aggressive mice, although LPS-stimulated production of this cytokine decreased after 10- and 20-day stress. The possible mechanisms of the changes in cytokine production are discussed.