160LEAD DEPRECIATES PASSIVE AVOIDANCE MEMORY RETENTION AND INJURES THE HIPPOCAMPUS IN WISTAR RATSThe objective of this study was to evaluate the effects of lead in male Wistar albino rats on learning and memory and hippocampus, a brain structure concerned with this function. 36 Wistar albino rats of were selected and divided into two groups „control‟ and „experimental‟ with equal numbers in each groups. Control rats were fed with saline and the experimental groups of rats were fed with pure lead (as lead acetate) through gastric gavage. A sub group of rats from each group were subjected to passive avoidance test on 15th, 30th and 45th day of feeding lead and then sacrificed for histological study of the hippocampus, basophilic stippling of red blood cells (RBC) and lead estimation in the blood. Data was analyzed by two tailed student‟s t-test using Graphpad in-Stat software. The blood lead level in experimental group was increased significantly and their RBC showed stippling. Passive avoidance test revealed impaired memory retention in the experimental group which was correlated with neurodegeneration in hippocampal sub regions. This study showed profound effects of lead on cognitive functions of the brain. To understand the mechanism of observed effects and to gain a better insight into the significance of our findings, needs further study.hsdsouza@gmail.comResearch652016Basophilic stippling,Blood lead level,Toxic metal,Cognitive functions,Differential Pulse Anodic Stripping VoltammetryHerman S. Dsouza,Muddanna S. Rao, Charanjeet S. GillDepartment of Biotechnology, School of Life Sciences, Manipal University, Manipal, 576104, India.,Department of Anatomy, Faculty of Medicine, Kuwait University, Safat-13110, Kuwait.,Department of Biotechnology, School of Life Sciences, Manipal University, Manipal, 576104, India.