Separate mesolimbic dopaminergic pathways mediate the opposing motivational effects of acute caffeine
Year: 2018
Type: dissertation
Abstract: Caffeine is the most commonly consumed psychoactive drug in the world, yet little is known about the neural substrates that underlie its rewarding and aversive properties. Using male Wistar rats in a place conditioning procedure, we showed that systemic caffeine at a low intraperitoneal dose of 2 mg/kg (or 100μM injected directly into the rostral, but not caudal, ventral tegmental area) induced reward. By contrast, high doses of systemic caffeine (10 and 30 mg/kg) produced aversions that were not recapitulated by a caffeine analog restricted to the periphery. We demonstrated that pharmacological blockade of dopamine receptors using α-flupenthixol injected into the nucleus accumbens shell, but not core, blocked caffeine reward. Conversely, α-flupenthixol injected into the nucleus accumbens core, but not shell, blocked caffeine aversions. Thus, our findings reveal two dopamine-dependent and functionally dissociable mechanisms for processing caffeine motivation that are segregated between nucleus accumbens subregions.
Source: TSpace (University of Toronto)
Author: Mandy Yee
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
OpenAlex ID: W2942308526