Tehran University of Medical Sciences Iranian Journal of Allergy, Asthma and Immunology 1735-1502 8 3 2009 09 15 Expression Changes of Serotonin Receptor Gene Subtype 5HT3a in Peripheral Blood Mononuclear Cells from Schizophrenic Patients Treated with Haloperidol and Olanzapin 135 139 Gholam Reza Shariati Department of Medical Genetic, National Institute for Genetic Engineering and Biotechnology (NIGEB), Ghasem Ahangari Department of Medical Genetic, National Institute for Genetic Engineering and Biotechnology (NIGEB), Arash Hossein-nezhad Endocrinology and Metabolism Research Center, Tehran University of Medical Sciences, Tehran, Iran Seyed Mohammad Asadi Department of Psychiatric, Rozbeh Hospital, Tehran University Medical sciences, Tehran, Iran Farzaneh Pooyafard Department of Psychiatric, Rozbeh Hospital, Tehran University Medical sciences, Tehran, Iran Hamid Reza Ahmadkhaniha Tehran Psychiatric Institute, Iran University of Medical Sciences, Tehran, Iran 2015 10 01 Serotonin receptors are involved in pathophysiology of schizophrenia and may mediate other neurotransmitter effects. We investigated serotonin receptors gene expression in peripheral blood mononuclear cells (PBMC) of naïve schizophrenic patients, before and after treatment. Also serotonin receptor gene expression was compared in two treatment groups including Haloperidol and Olanzapine. The PBMC was separated from whole blood by Ficoll-hypaque. The total cellular RNA was extracted and the cDNA was synthesized. This process was followed by real-time PCR using primer pairs specific for 5HT3a serotonin receptor mRNA and beta-actin as internal control. The results showed the presence of subtype of serotonin receptor in lymphocytes. Serotonin gene expression showed significant changes in Olanzapine treatment group which correlated with Clinical Global Impression (CGI) score improvement. In conclusion, the present study has shown that human PBMC express serotonin receptors 5HT3a. Moreover, clinical symptom improvement of Olanzapin may be demonstrated by a change in serotonin receptor gene expression. https://ijaai.tums.ac.ir/index.php/ijaai/article/view/247 https://ijaai.tums.ac.ir/index.php/ijaai/article/download/247/247