Involvement of Inhibitory Receptors in Modulating Dopamine Signaling and Synaptic Activity Following Acute Ethanol Exposure in Striatal Subregions
Journal article, 2015

Background: Alcohol acts on both inhibitory and excitatory receptor systems resulting in a net increase in dopamine output in the ventral striatum (nucleus accumbens [nAc]), which is implicated in drug reward. However, the dorsal striatum may also be involved in reward-related behaviors. The objectives of this study were to investigate the role of inhibitory receptors in modulating the acute effects of ethanol (EtOH) on dopamine release and synaptic activity in the shell region of the nAc (nAcS) and dorsolateral striatum (DLS). Methods: EtOH (300 mM) was administered via reversed microdialysis in the nAcS or DLS of Wistar rats following pretreatment with glycine or GABA(A) receptor antagonist strychnine and bicuculline, respectively. Dopamine content in dialysate samples was quantified using high-performance liquid chromatography. In addition, local field potential recordings were performed in the nAcS and DLS in slices from Wistar rats. Population spike (PS) amplitude was measured following treatment with EtOH (50 mM) in slices pretreated with strychnine or bicuculline. Results: Local EtOH increased dopamine levels in both regions, an effect that strychnine pretreatment inhibited in the nAcS. EtOH-induced increases in accumbal dopamine were not blocked by a low (5 mu M) concentration of bicuculline, but were inhibited by pretreatment with higher bicuculline concentrations. None of the antagonists administered in the DLS prevented the EtOH-induced dopamine increase. Field potential recordings in the nAcS showed that acute EtOH produced an increase in PS amplitude which was blocked by both strychnine and bicuculline. In the DLS, EtOH induced a decrease in PS amplitude which was not influenced by strychnine or bicuculline. Conclusions: The current results show that changes in striatal dopamine output and synaptic activity induced by acute EtOH administration are modulated by inhibitory receptors in a subregion-specific manner.

microdialysis

sensitive glycine receptors

extracellular dopamine

basal ganglia

ventral tegmental area

freely moving rats

mesolimbic dopamine

acetylcholine-receptors

nicotinic

Alcohol

nucleus-accumbens

in-vivo

GABA(A) Receptor

Nucleus Accumbens Shell

brain reward system

Substance Abuse

Glycine Receptor

Dorsolateral Striatum

Author

Rhona B. C. Clarke

University of Gothenburg

Bo Söderpalm

University of Gothenburg

Amin Lotfi

University of Gothenburg

Mia Ericson

University of Gothenburg

Louise Adermark

University of Gothenburg

Alcoholism: Clinical and Experimental Research

0145-6008 (ISSN) 1530-0277 (eISSN)

Vol. 39 12 2364-2374

Subject Categories

Neurosciences

Psychiatry

DOI

10.1111/acer.12895

PubMed

26614538

More information

Created

10/10/2017