Preliminary experiments to test the optimal doses of LPS to induce cognitive dysfunction and DFO to attenuate it by the Morris water maze test. Intracerebroventricular LPS reduced platform crossings (A) and distance around the plat (B) in reference memory test 1 day following microinjection after 5 days of training, and latency to plat (C) in working memory on post-injection days 1 to 3, 2 μg LPS in particular. DFO attenuated LPS-induced reduction of crossings (D) and distance around the platform (E), with 0.5 μg of DFO being more significant. Data are expressed as mean ± SE (n = 8). *P <0.05 vs. control; #P <0.05 vs. LPS. Con, control; DFO, deferoxamine; LPS, lipopolysaccharide; SE, standard error.