Item Details

title

The Effects of Nucleus Accumbens Neuropeptide Y Administration on α-Flupenthixol-Driven Motivational Impairment

author

Carney, Allison Elaine

abstract

Parkinson’s disease (PD) is a neurodegenerative disorder that is characterized, in part, by a depletion of nigrostriatal dopamine neurons that decreases dopamine signaling throughout the brain. PD patients experience an array of motor and behavioral impairments, one of the lesser understood of these symptoms being a dysregulation of motivated behavior. Striatal dopamine has a large influence on motivated behavior, as does Neuropeptide Y (NPY), a neurotransmitter whose expression is upregulated in the striatum of those with PD. The interplay of dopamine and NPY, and the effect this interaction has on motivated behavior is not well understood. Although there is evidence that NPY acts to protect against the neurodegenerative changes occurring in PD patients, it is not clear whether NPY may also reverse the motivational deficits caused by reduced dopamine signaling within the motivational pathway. Here, we measured motivation through use of a progressive ratio-2 paradigm. Male Sprague Dawley rats were treated with systemic injections of the dopamine antagonist, α-flupenthixol or a saline vehicle. Two hours following injections, they were given intra-accumbens injections of NPY (at 0, 156, or 235 pmol) and were placed were placed in operant chambers. Subjects were divided into two groups based on infusion location: the nucleus accumbens shell (n = 12) or the nucleus accumbens core (n=10). In both groups, α-flupenthixol impaired performance on the PR-2 task, replicating the results of prior studies. Interestingly, while NPY increased lever pressing and break point when injected into the nucleus accumbens shell, there were no effects of NPY upon infusion into the core. These data demonstrate that NPY in the nucleus accumbens shell can improve motivated behaviors that are impaired due to dopamine depletion, that these effects are site specific, and provide evidence that the upregulation of NPY in the nucleus accumbens shell may serve a compensatory role in the motivated behavior of PD patients.

subject

Dopamine Antagonism

Motivation

Neuropeptide Y

NPY

Nucleus Accumbens

Parkinson's Disease

contributor

Pratt, Wayne E (committee chair)

Lack, Anna K (committee member)

Masicampo, Melissa L (committee member)

date

2020-05-29T08:36:11Z (accessioned)

2022-05-28T08:30:15Z (available)

2020 (issued)

degree

Psychology (discipline)

embargo

2022-05-28 (terms)

identifier

http://hdl.handle.net/10339/96854 (uri)

language

en (iso)

publisher

Wake Forest University

type

Thesis