Brief CommunicationLipopolysaccharide and Interleukin-1 Depress Food-Motivated Behavior in Mice by a Vagal-Mediated Mechanism
Abstract
In order to assess the role of vagal nerve afferents in the decrease in food-motivated behavior induced by proinflammatory cytokines, the effects of lipopolysaccharide (LPS, 400 μg/kg ip) and recombinant human interleukin-1β (IL-1, 750-1500 ng/mouse ip) were tested on nose poke for food in vagotomized and sham-operated mice. Subdiaphragmatic vagotomy attenuated the decrease in response rate induced by IL-1 and LPS. These results suggest that the peripheral immune message is transmitted to the brain via a neural rather than a humoral pathway.
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Tanycytes form the brain barrier that mediates the anorexic effect of systemic inflammation in the hypothalamus.
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