en Learning and Memory, Dementia, Alzheimer پژوهشي Research Article <div style="text-align: justify;"><strong>Background: </strong>The abuse of anabolic androgenic steroids is associated with changes in learning and memory function.&nbsp;&nbsp;<br> <strong>Objectives:</strong> Nandrolone is one of the most popular anabolic androgenic steroid compounds abused by adolescents. Previous studies suggested that nandrolone changes learning and memory; however, the underlying mechanism is unclear. Therefore, the present study evaluated the role of P450 aromatase and castration on spatial learning and memory changes induced by nandrolone in adolescent male rats.&nbsp;<br> <strong>Materials and Methods:</strong> This study used the Morris water maze to evaluate spatial learning and memory. The experimental groups received DMSO as control groups and different doses of nandrolone (10, 30 and 60 &micro;g/ 2.5 &micro;L), anastrozole (2.5, 5 and 10 &micro;g/ 2.5&micro;L), and anastrozole (2.5 &micro;g/ 2.5 &micro;L) + nandrolone (60 &micro;g/ 2.5 &micro;l) all days before the training. The rats of ninth and tenth groups were castrated and treated with 2.5 &micro;L of DMSO and nandrolone (60 &micro;g), respectively for 4 days.&nbsp;<br> <strong>Results:</strong> Both nandrolone and anastrozole decrease in escape latency and traveled distance (P<0.05). Furthermore, the escape latency and traveled distance in the group which received anastrozole (2.5 &micro;g) + nandrolone (60 &micro;g) were significantly lower than that of the control group (P<0.05). Additionally, castration had no effect on escape latency and traveled distance, but it abolished the improvement effect of ND.&nbsp;<br> <strong>Conclusion: </strong>Nandrolone improved spatial learning and memory, but castration could abolish nandrolone-induced spatial learning and memory improvement. These results indicate the effect of nandrolone on learning induced by changes in gonadal function.</div> Nandrolone, Spatial memory, Anastrozole 153 162 http://ajnpp.umsha.ac.ir/browse.php?a_code=A-10-137-1&slc_lang=en&sid=1 Zahra Salimi zahra.salimi.bio@gmail.com 1003194753284600989 1003194753284600989 No Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran. Farshad Moradpour fmoradpour@kums.ac.ir 1003194753284600990 1003194753284600990 Yes Fertility and Infertility Research Center, Health Technology Institute, Kermanshah University of Medical Sciences, Kermanshah, Iran. Lotfollah Khajehpour khlotfollah.bio@gmail.com 1003194753284600991 1003194753284600991 No Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran. Ahmad Ali Moazedi moazedia@gmail.com 1003194753284600992 1003194753284600992 No Department of Biology, Faculty of Science, Shahid Chamran University of Ahvaz, Ahvaz, Iran. Ali Pourmotabbed a.pourmotabbed@kums.ac.ir 1003194753284600993 1003194753284600993 No Department of Physiology, Faculty of Science, Kermanshah University of Medical Sciences, Kermanshah, Iran.