Iranian Journal of Basic Medical Sciences (Mar 2019)

Effect of intracerebroventricular injection of GABA receptors antagonists on morphine-induced changes in GABA and GLU transmission within the mPFC: an in vivo microdialysis study

  • Effat Ramshini,
  • Hojjat allah Alaei,
  • Parham Reisi,
  • naser Naghdi,
  • Hossein Afrozi,
  • Samaneh Alaei,
  • Maryam Alehashem,
  • Shahrzad Eftekharvaghefi

DOI
https://doi.org/10.22038/ijbms.2019.28478.6925
Journal volume & issue
Vol. 22, no. 3
pp. 246 – 250

Abstract

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Objective(s): Many studies have focused on ventral tegmental area than of other mesocorticolimbic areas, and implicated a key role for the medial prefrontal cortex (mPFC) in the development of addictive behaviors. So far, the role of gamma-aminobutyric acid (GABA) receptors in the discriminative properties of morphine has received little attention and few studies evaluated the role of these receptors in drug dependence. Hence, we investigated the role of this receptor on morphine- induced GABA/ glutamate (GLU) changes in the mPFC following morphine administration using in vivo microdialysis.Materials and Methods: In this study, 60 rats weighing 270-300 g were divided into six groups. First, microdialysis probe was inserted into the mPFC and was perfused with artificial cerebrospinal fluid and collected the baseline samples in all groups. In saline and morphine groups, the saline, in phaclophen and (phaclofen+morphine) groups, phaclofen (100 nmol), and in bicuculline and (bicuculline+morphine) groups, bicuculline (20 nmol) was injected intracerebroventricular. In saline, phaclofen and bicuculline groups 20 min later, animals received saline (0.2 ml, IP) and others groups received morphine (20 mg/kg, IP).Results: Our results showed that morphine increased the average concentration of GABA and decreased the concentration of GLU within mPFC. Pretreatment with phaclofen and bicuculline 20 min before morphine administration had no effect on GABA and GLU release for 100 min.Conclusion: The present study indicated that morphine influence the GABA and GLU transmission in mPFC. Therefore evaluation of neurochemistry changes of this neural circuitry may provide further insight into the mechanisms underlying drug dependence.

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