en Blood and Immune System Blood and Immune System Experimental research article Experimental research article <div style="text-align: justify;"><span class="fontstyle0"><strong>Introduction:</strong> </span><span class="fontstyle2">Neuroinflammation is a primary pathophysiological condition that is associated with cognitive impairment and neurodegenerative diseases. The present study was designed to evaluate the effects of enriched environment (EE) on passive avoidance (PA) memory impairment caused by lipopolysaccharide (LPS) induced neuroinflammation. </span><strong><span class="fontstyle0">Methods: </span></strong><span class="fontstyle2">Twenty-eight male Wistar rats were assigned into the following groups: 1, control; 2, control+ EE; 3, LPS and 4, LPS+ EE. LPS injection (1mg/kg/i.p.) was done on days 1, 3, 5 and 7 of experiment. Two different housing conditions were used in this experiment, including a standard environment house and an enriched environment house. The passive avoidance task was used to examine animals learning and memory performance. The hippocampal level of interleukin-6 (IL-6) and brain-derived neurotrophic factor (BDNF) was also measured using sandwich-ELISA method. </span><strong><span class="fontstyle0">Results: </span></strong><span class="fontstyle2">Obtained data indicated that LPS significantly impaired passive avoidance memory, decreased the step-through latency and increased the time spent in the dark compartment of the LPS treated group compared to the control group. On the other hand, EE housing could significantly ameliorate memory impairment. Hippocampal IL-6 level was increased and BDNF was decreased in the LPS group, whereas EE could decrease and increase IL-6 and BDNF levels in the LPS+EE group, respectively. </span><strong><span class="fontstyle0">Conclusion: </span></strong><span class="fontstyle2">EE should probably be considered as an alternative strategy in neuroinflammatory diseases to minimize the memory impairment.</span></div> Inflammation, Enriched environment, Memory, Passive avoidance 127 137 http://ppj.phypha.ir/browse.php?a_code=A-10-1586-1&slc_lang=en&sid=1 Arman Keymoradzadeh 3200319475328460030906 3200319475328460030906 No Student Research Committee, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran Mojtaba Hedayati Ch 3200319475328460030907 3200319475328460030907 No Department of Microbiology, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran Mahmood Abedinzade 3200319475328460030908 3200319475328460030908 No Medical Biotechnology Research Center, School of Nursing, Midwifery and Paramedicine, Guilan University of Medical Sciences, Rasht, Iran Behrooz Khakpour-Taleghani Khakpour@gums.ac.ir 3200319475328460030909 3200319475328460030909 Yes Neuroscience Research Center, School of Medicine, Guilan University of Medical Sciences, Rasht, Iran