EN
Chronic stress, by initiating changes in the hypothalamic-pituitaryadrenal (HPA) axis and the immune system, acts as a trigger for neuropsychiatric disorders. Brain-derived neurotrophic factor (BDNF) is highly involved in regulation of HPA activity. The aim of the study was to investigate the influence of acute immunostimulation on the of BDNF in the hypothalamus and pituitary of rats subjected to chronic stress. Female Sprague-Dawley rats were subjected to 4-week stress, including phases of isolation and crowding, in an unpredictable manner. On the last day of the experiment rats being at the estrus phase were injected ip. with LPS (1 mg/kg/2 ml) or saline. Six hours later the brain structures were rapidly isolated. QRT-PCR experiments were performed using TaqMan Gene Expression Assays. The BDNF concentration was measured with a conventional ELISA assay. In the hypothalamus and pituitary of LPS-treated stressed rats BDNF mRNA expression was decreased in comparison to saline-treated stressed group. We concluded that chronic stress and inflammation have synergistic deleterious influence on BDNF in the studied structures.