Cue- and reward-related dendritic and presynaptic plasticity of nucleus accumbens neurons in male and female sign-tracker rats.
Year: 2023
Type: preprint
Abstract: For a subset of individuals known as sign-trackers, discrete Pavlovian cues associated with rewarding stimuli can acquire incentive properties and exert control over behaviour.Because responsiveness to cues is a feature of various neuropsychiatric conditions, rodent models of signtracking may prove useful for exploring the neurobiology of individual variation in psychiatric vulnerabilities.Converging evidence points towards the involvement of dopaminergic neurotransmission in the nucleus accumbens core in the development of sign-tracking; yet, whether this phenotype is associated with specific accumbal postsynaptic properties is unknown.Here we examined dendritic spine structural organisation, as well as presynaptic and postsynaptic markers of activity, in the nucleus accumbens core of male and female rats following a Pavlovian conditioned approach procedure.Data suggest that re-exposure to the food cue resulted in denser and longer spines in the NAc core of individuals that may have attributed more incentive salience to the cue.Crucially, the presence of the reward during cue re-exposure also impacted on spine morphology.In addition, male and female rats differed in behaviour and the expression of a marker of presynaptic activity (synaptophysin).Interestingly, the acquisition of conditioned responses in female sign-trackers was not affected by the oestrous cycle.This work supports the suggestion that individual variations in Pavlovian responses are associated with differences in neuronal plasticity of the nucleus accumbens core, whilst highlighting the importance of studying the behaviour and neurobiology of both male and female rats. Graphical
Institutions: University of Sussex, King's College London, The Open University
Language: English
Subfield: Cellular and Molecular Neuroscience
Field: Neuroscience
Domain: Life Sciences
Open Access status: green
Funder: University of Sussex
OpenAlex ID: W4384155141