Peripheral Administration of Tumor Necrosis Factor-Alpha Induces Neuroinflammation and Sickness but Not Depressive-Like Behavior in Mice

Figure 4

TNF-α causes sickness, but no clear depressive-like behavior. Systemic injection of TNF-α caused body weight loss ((a)-(b)), reduced locomotor activity in the open field test ((c)-(d)), and decreased total fluid intake in the sucrose preference test (g). Measures of behavioral despair in the forced swim test were not affected by administration of TNF-α ((e)-(f)). A high dose of TNF-α did decrease sucrose preference in the SPT (h) but this can be considered biologically irrelevant due to the overlapping time course of sickness. The dashed line in the sucrose preference test indicates the chance level (50%) for sucrose preference. Please note that the -axis does not start at 0 for the forced swim and sucrose preference test data. Graphs are plotted as mean ± SEM ( per group, except for 1000 μg/kg TNF-α). Data were analyzed by rmANOVA followed by independent samples -test. compared to 0 μg/kg TNF-α.

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