Altered Social behavior in brain tumor rats model Lusine Hovhannisyan, Manushak Avagyan, Vahe Mkrtchyan, Elya Minasyan, Tamara Harutyunyan, Mariam Movsisyan, Senik Matinyan Lusine.hovhannisyan@meduni.am Introduction Objective Different studies evidence that rats act socially and value social relations, whereas brain tumors have deleterious effect on brain neurological and cognitive functions. The purpose of this study is to evaluate the social behavior of rats implanted with brain tumor. Cyclosporine immunosuppressed rats with sarcoma 105 injected in hippocampal region are used as brain tumor model and specific changes in social behavior were tested.   Methods Adult albino rats weighting 100+/- 5 grams were immunosuppressed with cyclosporine 25mg/kg i/p 48h prior to surgery and during all days of the experiment[1]. Rats were anesthetized with Nembutal 40 mg/kg i.p. and placed on stereotaxis frame[2]. The tumor cells were injected in hippocampus (AP –3.5 mm, ML 3.0 mm, DV 2.3 mm)[3]. The control group was injected with isotonic saline solution. Social behaviour was assessed on day 7 of the experiment using the social interaction test[4]. The rats were sacrificed on day 10 of experiment and morphological analysis was conducted to validate tumor location. Results and discussion Animals with brain tumor showed significantly higher social and empathetic behavior. This results may be due to lesion induced impairment and stress. Conclusion We conclude that this model can be successfully used for assessment for social behavior which can be feasibly measured. References 1. Matthew M. Goodman, Jerry L. McCullough, Catherine A. Biren, Ronald J. Barr, A Model of Human Melanoma in Cyclosporine-Immunosuppressed Rats, Journal of Investigative Dermatology, Volume 88, Issue 2, 1987, Pages 141-144, ISSN 0022-202X, http://dx.doi.org/10.1111/1523-1747.ep12525289. 2. Rison RA. A guide to writing case reports for the Journal of Medical Case Reports and BioMed Central Research Notes. Journal of Medical Case Reports. 2013;7:239. doi:10.1186/1752-1947-7-239.. Routtenberg A. Pentobarbital anesthesia of albino rats. Journal of the Experimental Analysis of Behavior. 1968;11(1):52. doi:10.1901/jeab.1968.11-52. 3․ Jankowsky JL, Derrick BE, Patterson PH. Cytokine Responses to LTP Induction in the Rat Hippocampus: A Comparison of In Vitro and In Vivo Techniques. Learning & Memory. 2000;7(6):400-412. 4․ Becker A1, Peters B, Schroeder H, Mann T, Huether G, Grecksch G., Ketamine-induced changes in rat behaviour: A possible animal model of schizophrenia, Prog Neuropsychopharmacol Biol Psychiatry. 2003 Jun;27(4):687-700. http://www.virginiahughes.com/category/conference-coverage/page/2/ http://journal.frontiersin.org/article/10.3389/fnbeh.2014.00169/full