Ghrelin Recruits Specific Subsets of Dopamine and GABA Neurons of Different Ventral Tegmental Area Sub-nuclei. (10th November 2018)

• Record Type: Journal Article
• Authors: Cornejo, María Paula; Barrile, Franco; De Francesco, Pablo Nicolás; Portiansky, Enrique Leo; Reynaldo, Mirta; Perello, Mario
• Is Part Of: Neuroscience. Volume 392(2018)
• Page Start: 107
• Page End: 120
• Publication Date: 2018-11-10
• Subjects: Acb accumbens -- AcbC Acb core -- CLi caudal linear -- DA dopamine -- GABA gamma-aminobutiric acid -- GHSR growth hormone secretagogue receptor -- IF interfascicular -- LAcbSh lateral Acb shell -- MAcbSh medial Acb shell -- PBP parabrachial pigmented -- PN paranigral -- RLi rostral linear -- TH tyrosine hydroxylase -- VTA ventral tegmental area; mesolimbic pathway -- locomotor activity -- food intake -- dopamine -- GABA; Neurochemistry -- Periodicals; Neurophysiology -- Periodicals; Neurology -- Periodicals; Neurochimie -- Périodiques; Neurophysiologie -- Périodiques; Neurochemistry; Neurophysiology; Electronic journals; Periodicals; Electronic journals; 612.8
• DOI: 10.1016/j.neuroscience.2018.09.027
• Languages: English
• ISSNs: 0306-4522

Abstract

Highlights: Ghrelin binding cells were present in most VTA sub-nuclei. SC-injected ghrelin did not affect locomotor activity or c-Fos in the VTA. ICV- and intraVTA-injected ghrelin increased locomotor activity. ICV- and intraVTA-injected ghrelin increased c-Fos in non-DA neurons and in a subset of DA neurons of the VTA. ICV-injected ghrelin increased c-Fos in a subset of GABA neurons of the VTA. Abstract: Ghrelin is a stomach-derived hormone that regulates rewarding behaviors and reinforcement by acting on the ventral tegmental area (VTA). The VTA is a complex midbrain structure mainly comprised of dopamine (DA) and gamma-aminobutiric acid (GABA) neurons that are distributed in several VTA sub-nuclei. Here, we investigated the neuroanatomical distribution and chemical phenotype of ghrelin-responsive neurons within the VTA. In wild-type mice, we found that: (1) ghrelin binding cells are present in most VTA sub-nuclei but not in its main target, the nucleus accumbens (Acb); (2) systemically injected ghrelin increases food intake but does neither affect locomotor activity nor the levels of the marker of neuronal activation c-Fos in the VTA sub-nuclei; (3) centrally injected ghrelin increases food intake, locomotor activity and c-Fos levels in non-DA neurons of all VTA sub-nuclei; (4) intra-VTA-injected ghrelin increases food intake, locomotor activity and c-Fos levels in non-DA neurons of all VTA sub-nuclei; (5) both centrally and intra-VTA-injected ghrelin increase c-Fos levels in DA neurons of the parabrachial pigmented VTA sub-nucleus. In genetically modified mice in which a subset of GABA neurons expresses the red fluorescent protein tdTomato, we found that centrally injected ghrelin increases c-Fos levels in GABA neurons of the interfascicular VTA sub-nucleus. These results suggest that ghrelin can recruit specific subsets of VTA neurons in order to modulate food intake and locomotor activity.