eng Oriental Scientific Publishing Company Biomedical and Pharmacology Journal 0974-6242 2015-12-28 8 2 1399 1406 10.13005/bpj/900 5885 article Bakhtiar Ebrahimirad 1 Gholamali Jelodr 1 Department of Physiology, Faculty of Veterinary, University of Shiraz, Shiraz, Iran. Based on biological views, behavioral changes are associated with the amount of neurotransmitters and hormones. In this regard, the current article intends to perform a comparative analysis of the amount of the hormones including serotonin, testosterone, and cortisol in normal and aggressive subjects. Therefore, 70 patients (age range 20 to 40 years) were studied in two groups of aggressive and normal that none of them had the history of addiction, cardiovascular and intestinal diseases. To examine aggressive behavior, two methods including Arnold H. Buss and Mark Perry Aggression Questionnaires and also interview technique were utilized. The aggressive people were selected, in collaboration with a psychiatrist, among incarcerated people and also those referred to hospital ICU who mostly suffered from non-penetrating and penetrating trauma following injuries and clashes. To choose normal people, a questionnaire was distributed among all the people of all strata of society, and eventually after a review of the questionnaire, two groups of normal and aggressive subjects were selected. Blood samples were taken from all persons and the amount of serotonin, testosterone, and cortisol were measured by ELISA. Then, the data obtained were compared using stastical t-tests of the two independent groups and Pearson’s correlation (Software SPSS 20). The results showed that there exists a significant difference between the mean levels of serotonin, testosterone and cortisol in the normal and aggressive subjects, and the in the aggressive subjects, a drop in serotonin, an increase in testosterone and also a reduction in cortisol could be observed in comparison to the normal subjects. https://biomedpharmajournal.org/vol8no2/a-comparative-analysis-of-serum-levels-of-serotonin-testosterone-and-cortisol-in-normal-and-aggressive-individuals/ Aggressiveness Hormone Serotonin Cortisol Testosterone