Dopamine Receptor Gene Expression Changes in Peripheral Blood Mononuclear Cells from Schizophrenic Patients Treated with Haloperidol and Olanzapine

Abstract

We investigated dopamine receptor gene expression in peripheral blood mononuclear cells of schizophrenic patients before and after treatment. Also dopamine receptor genes expression profile was compared in two treatment groups including haloperidol and olanzapine. The peripheral blood mononuclear cells were 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 polymerase chain reaction using primer pairs specific for five dopamine receptor mRNAs and β-actin as internal control. The results show the presence of all types of dopamine receptor in lymphocytes. Dopamine receptor gene expression profile in dopamine receptor D2 gene and dopamine receptor D4 gene showed significant changes that were correlated with the type of treatment and Clinical Global Impressions score improvement. In conclusion, the present study shows that human lymphocytes express dopamine receptor D1–D5 genes. Moreover, investigated dopamine receptors gene expression in peripheral blood mononuclear cells of schizophrenic patients correlated with clinical symptom improvement.