Effects of intra-accumbal or intra-prefrontal cortex microinjections of adenosine 2A receptor ligands on responses to cocaine reward and seeking in rats
Year: 2018
Type: article
Abstract: Many studies indicated that adenosine via its A 2A receptors influences the behavioral effects of cocaine by modulating dopamine neurotransmission. The hypothesis was tested that A 2A receptors in the nucleus accumbens (NAc) or the prefrontral cortex (PFc) may modulate cocaine reward and/or cocaine seeking behavior in rats. The effects of local bilateral microinjections of the selective A 2A receptor agonist CGS 21680 or the A 2A receptor antagonists KW 6002 and SCH 58261 were investigated on cocaine self-administration on reinstatement of cocaine seeking. The intra-NAc shell, but not intra-infralimbic PFc, administration of CGS 21680 significantly reduced the number of active lever presses and the number of cocaine (0.25 mg/kg) infusions. However, tonic activation of A 2A receptors located in the NAc or PFc did not play a role in modulating the rewarding actions of cocaine since neither KW 6002 nor SCH 58261 microinjections altered the cocaine (0.5 mg/kg) infusions. The intra-NAc but not intra-PFc microinjections of CGS 21680 dose- dependently attenuated the reinstatement of active lever presses induced by cocaine (10 mg/kg, i.p.) and the drug-associated combined conditioned stimuli using the subthreshold dose of cocaine (2.5 mg/kg, i.p.). On the other hand, the intra-NAc pretreatment with SCH 58261, but not with KW 6002, given alone evoked reinstatement of cocaine seeking behavior. The results strongly support the involvement of accumbal shell A 2A receptors as a target, the activation of which exerts an inhibitory control over cocaine reward and cocaine seeking.
Source: Psychopharmacology
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: hybrid
Estimated APC paid: $4,390
Awards: G1652231044, G5143620599
OpenAlex ID: W2901418979