GABAB receptors within the ventral tegmental area are involved in the expression and acquisition of morphine-induced place preference in morphine-sensitized rats

Summary, in English

The influence of intra-ventral tegmental area administration of gamma-amino-butyric-acid-B (GABAB) receptor agonist and antagonist on the expression and acquisition of morphine-induced conditioned place preference (CPP) in morphine-sensitized female rats was examined. Our pilot experiment showed that subcutaneous administration of morphine-(2.5, 5 and 7.5 mg/kg) induced CPP. Administration of one dose daily morphine (5 mg/kg) for 3 days followed by 5 days rest, enhanced the conditioning induced by ineffective doses of morphine (0.25, 0.5 and 1 mg/kg). Injections of GABAB receptor agonist, baclofen, (1.5 and 12 μg/rat) reduced the expression of morphine CPP whereas the dose of 6 μg/rat of the drug increased it. Baclofen also significantly reduced the acquisition of morphine CPP in morphine-sensitized animals. Administration of GABAB receptor antagonist, CGP 35348, significantly reduced the expression (12 μg/rat) and acquisition (1.5, 6 and 12 μg/rat) of morphine CPP in morphine-sensitized animals.

In conclusion, results confirmed the importance of GABAB receptors within the ventral tegmental area of morphine CPP in morphine-sensitized female rats.

• Author: Hedayat Sahraei; Leila Etemadi; Parvin Rostami; Ali Pourmotabbed; Mohammad-Reza Zarrindast; Jamal Shams; Hassan Ghoshooni; Ali Noroozzadeh; Behnaz Esfandiari; Seyed Hossein
• Publishing year: 2009
• Language: English
• Pages: 409-416
• Publication/Series: Pharmacology, Biochemistry and Behavior
• Volume: 91
• Issue: 3
• Links: http://dx.doi.org/10.1016/j.pbb.2008.08.015
• Document type: Journal article
• Publisher: Elsevier
• Topic: Neurosciences
• Keywords: Sensitization; Morphine; GABAB receptor subtypes; Conditioned place preference; Rat
• Status: Published
• ISBN/ISSN/Other: ISSN: 1873-5177