Tags

Type your tag names separated by a space and hit enter

Systemic administration of ghrelin increases extracellular dopamine in the shell but not the core subdivision of the nucleus accumbens.
Neurochem Int. 2009 Feb; 54(2):89-94.NI

Abstract

The gut-hormone ghrelin endogenously binds to the ghrelin receptor (GHS-R) to promote foraging and feeding behaviours mainly via the hypothalamic arcuate nucleus (ARC). GHS-Rs are also expressed in midbrain dopaminergic neurons of the ventral tegmental area (VTA) suggesting that ghrelin may modulate the mesolimbic dopamine (DA) system. In support of this hypothesis, previous results have shown that intraventricular administration of ghrelin in rats increases DA levels in the nucleus accumbens (NAc). In the present study, the systemic doses of ghrelin capable of triggering central activation were first determined, and growth hormone (GH) levels were used as a marker of ghrelin-induced activation. Similar dose regimen was then used to measure ghrelin-induced effects on extracellular levels of monoamines in the shell and core subdivisions of the NAc using microdialysis in freely moving rats. We show that subcutaneous (s.c.) administration of ghrelin produced an increase in basal plasmatic ghrelin concentrations that was paralleled by enhanced GH secretion. In addition, a significant increase in extracellular levels of DA was observed specifically in the NAc shell, with no effect in the core subdivision. Extracellular serotonin (5-HT) levels were also affected in the shell subregion, but without reaching statistical significance. Increased extracellular DA levels in the NAc shell have been typically associated with the acute reinforcing effects of addictive drugs. The present findings therefore suggest that systemic ghrelin may modulate the valence of reinforcers such as food and drugs of abuse by interfering with mesolimbic DA activity.

Authors+Show Affiliations

Department of Biology, Neurosciences CEDD, GlaxoSmithKline Medicines Research Centre, Via A. Fleming 4, 37135 Verona, Italy. davide.2.quarta@gsk.comNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info availableNo affiliation info available

Pub Type(s)

Journal Article

Language

eng

PubMed ID

19118592

Citation

Quarta, Davide, et al. "Systemic Administration of Ghrelin Increases Extracellular Dopamine in the Shell but Not the Core Subdivision of the Nucleus Accumbens." Neurochemistry International, vol. 54, no. 2, 2009, pp. 89-94.
Quarta D, Di Francesco C, Melotto S, et al. Systemic administration of ghrelin increases extracellular dopamine in the shell but not the core subdivision of the nucleus accumbens. Neurochem Int. 2009;54(2):89-94.
Quarta, D., Di Francesco, C., Melotto, S., Mangiarini, L., Heidbreder, C., & Hedou, G. (2009). Systemic administration of ghrelin increases extracellular dopamine in the shell but not the core subdivision of the nucleus accumbens. Neurochemistry International, 54(2), 89-94. https://doi.org/10.1016/j.neuint.2008.12.006
Quarta D, et al. Systemic Administration of Ghrelin Increases Extracellular Dopamine in the Shell but Not the Core Subdivision of the Nucleus Accumbens. Neurochem Int. 2009;54(2):89-94. PubMed PMID: 19118592.
* Article titles in AMA citation format should be in sentence-case
TY - JOUR T1 - Systemic administration of ghrelin increases extracellular dopamine in the shell but not the core subdivision of the nucleus accumbens. AU - Quarta,Davide, AU - Di Francesco,Carla, AU - Melotto,Sergio, AU - Mangiarini,Laura, AU - Heidbreder,Christian, AU - Hedou,Gael, Y1 - 2008/12/11/ PY - 2008/10/14/received PY - 2008/11/14/revised PY - 2008/12/02/accepted PY - 2009/1/3/entrez PY - 2009/1/3/pubmed PY - 2009/5/2/medline SP - 89 EP - 94 JF - Neurochemistry international JO - Neurochem Int VL - 54 IS - 2 N2 - The gut-hormone ghrelin endogenously binds to the ghrelin receptor (GHS-R) to promote foraging and feeding behaviours mainly via the hypothalamic arcuate nucleus (ARC). GHS-Rs are also expressed in midbrain dopaminergic neurons of the ventral tegmental area (VTA) suggesting that ghrelin may modulate the mesolimbic dopamine (DA) system. In support of this hypothesis, previous results have shown that intraventricular administration of ghrelin in rats increases DA levels in the nucleus accumbens (NAc). In the present study, the systemic doses of ghrelin capable of triggering central activation were first determined, and growth hormone (GH) levels were used as a marker of ghrelin-induced activation. Similar dose regimen was then used to measure ghrelin-induced effects on extracellular levels of monoamines in the shell and core subdivisions of the NAc using microdialysis in freely moving rats. We show that subcutaneous (s.c.) administration of ghrelin produced an increase in basal plasmatic ghrelin concentrations that was paralleled by enhanced GH secretion. In addition, a significant increase in extracellular levels of DA was observed specifically in the NAc shell, with no effect in the core subdivision. Extracellular serotonin (5-HT) levels were also affected in the shell subregion, but without reaching statistical significance. Increased extracellular DA levels in the NAc shell have been typically associated with the acute reinforcing effects of addictive drugs. The present findings therefore suggest that systemic ghrelin may modulate the valence of reinforcers such as food and drugs of abuse by interfering with mesolimbic DA activity. SN - 0197-0186 UR - https://www.unboundmedicine.com/medline/citation/19118592/Systemic_administration_of_ghrelin_increases_extracellular_dopamine_in_the_shell_but_not_the_core_subdivision_of_the_nucleus_accumbens_ L2 - https://linkinghub.elsevier.com/retrieve/pii/S0197-0186(08)00198-8 DB - PRIME DP - Unbound Medicine ER -