Abstract: | Heme oxygenase‐1 (HO‐1) is a stress protein expressed in various pathological conditions associated with oxidative stress. Brain HO‐1 expression and activity in response to LPS treatment showed regional variability with the highest levels in the substantia nigra (SN) and hippocampus. HO‐1 induction by LPS was redox‐sensitive and associated with increased levels of NO synthase and arginase, two proteins involved in the regulation of cellular redox state. Brain HO‐2 and HO‐3 expression, studied by quantitative RT‐PCR, did not show significant changes. Our data suggest an interaction between NO and the HO system in the brain after LPS treatment. As SN and hippocampus are involved in Parkinson's and Alzheimer's diseases, understanding interaction of these proteins in the brain will help to elucidate the mechanisms involved in neurodegeneration. |