Estudo de alterações comportamentais e neuroinflamatórias induzidas pela administração sistêmica de lipopolissacarídeo de escherichia coli em camundongos

Abstract

Based on evidences that systemic administration of lipopolysaccharide (LPS) in animals can trigger time-dependent pathophysiological changes, which together are named sickness behavior and depression, we sought to determine by immune challenge with systemic administration of LPS (0.5 mg / kg, ip) in male mice, the behavioral changes on parameters such as: behavior related to depression and anxiety, pre-pulse inhibition (PPI), working memory, motor coordination and locomotor activity, 1, 5 and 24h after administration of endotoxin, respectively, the time points for the development of disease and behavior depressive-like, and neurochemical by evaluating the levels of cytokines (TNF and IL1β) in the blood (plasma) and brain areas (prefrontal cortex (PFC), hippocampus (HC) and striatum (ST). Moreover, were measured brain levels of nitrite. Changes 1.5 h post-LPS were hypolocomotion, behaviors related to depression and anxiety, working memory deficits, accompanied by increases in levels of IL-1β in plasma and PFC, TNF a and reductions in plasma levels of nitrite in ST and PFC. Twenty-four hours after LPS, depression-related behavior and deficits of working memory remained, while the levels of PPI reduced significantly accompanied by an increase in the content of IL-1β in the PFC and decreased levels of nitrite in HC, ST and PFC. Taken together, the results of this study provide further evidence for changes in levels of PPI behavior similar to LPS-induced depression and for the involvement of nitric oxide in behavior similar to depression induced by LPS in mice.