The Role Of NMDA Receptors In Tolerance And Dependence To The Morphine In The Striatum And The Prefrontal Cortex Of Rat Brain

 

Fatemeh Rafieenia1*, Shamseddin Ahmadi2, Jalal Rostamzadeh2, Sabrieh Amini3, Garshasb Rigi Cheshmehali4

 

1M.Sc in Cellular and Molecular Biology, University of Kurdistan, Sanandaj, Iran

2  Assistant professor of  Department of Biological Science & Biotechnology, Faculty of Science, University of Kurdistan, Sanandaj, Iran

3  Assistant professor  of  Department of Biological, Faculty of Science, Islamic Azad University, sanandaj branch, iran

4 PhD student in Molecular Genetics in National Institute of Genetic Engineering and Biotechnology, Tehran, iran

 

Introduction: N-Methyl-D-Aspartate (NMDA) receptors have important roles in learning, memory formation, tolerance and dependence to the morphine.

Aim: In the present study, after induction of morphine dependence in male wistar rats, changes in gene expression of NR1 subunit of NMDA receptors, the main subunit of these receptors, in the striatum and the prefrontal cortex of rat brain were examined.

Material and Methods: For induction of morphine dependence, a dose of 10 mg/kg of morphine was administrated intraperitoneally for seven consecutive days. Control group received saline replace to morphine similarly. Tolerance to the morphine was examined by a hot plate test of analgesia, 1 day after the final repeated administrations. A semi-quantative RT-PCR was used for evaluating gene expression in different periods after withdrawal.

Results: The results showed that the level of mRNA of NR1 in the striatum on day 1 after the final repeated administrations of morphine was significantly increased, while in the prefrontal cortex was significantly decreased. on the other interval times of 3, 7, 14 and 21 days after the final repeated administrations of morphine, changes in the gene expression in the two areas compared with control group were not significant, and almost returned to the basal level.

 

Keywords: Morphine, NMDAR, Striatum, Prefrontal,cortex