TY - JOUR TI - Effect of Staphylococcal enterotoxin A and tumor necrosis factor alpha on exploratory behaviors toward novel stimuli DO - https://doi.org/doi:10.7282/t3-0pzt-nt17 PY - 2019 AB - Staphylococcal enterotoxin A (SEA) is a superantigen that stimulates T cells. It has well-characterized neurobiological and endocrine effects, which have been shown to rely on the cytokine, tumor necrosis factor alpha (TNFα). We tested the effect of SEA and TNFα on mouse exploratory behavior toward a novel stimulus using multiple protocols. To test the effects of SEA challenge, novel object stimuli with and without a familiar object were presented to male C57BL/6 mice, and the mice were given one or more days to explore the familiar object before the test. When exposed to a novel object together with a familiar object, SEA-challenged mice displayed more immobile episodes and duration when observing the novel object. However, when the animals were given multiple trials to explore the novel object, the increased immobility was reduced. When the animals were tested in a different procedure involving a larger open field apparatus without the presence of the familiar object, mice showed less exploration to the novel object when treated with SEA. This was observed to be age-dependent, with older mice (10 months) showing a greater effect relative to younger mice (3 months). SEA stimulates T-cells and increases the level of tumor necrosis factor alpha (TNF-α). Consequently, we conducted additional experiments in which the effects of central TNFα infusion was tested in a series of conditions looking at an object, food and social mate novelty. The results showed that TNF-α increased the exploratory behavior in the open field with the presence of a novel object, and decreased exploration and consumption of a novel diet. Overall, it was concluded that TNF-α, a major cytokine released in response to T-cell activation by SEA, affects the exploratory behavior of mice in multiple dimensions. Future studies should determine whether SEA effects involve TNF actions operating within the brain. KW - SEA KW - Psychology KW - Staphylococcal infections KW - Tumor necrosis factor LA - English ER -