title: Striatal medium spiny neurons terminate in a distinct region in the lateral hypothalamic area and do not directly innervate orexin/hypocretin- or melanin-concentrating hormone-containing neurons.
abstract: Neuronal circuits including medium spiny neurons (MSNs) in the nucleus accumbens (NAc) and melanin-concentrating hormone (MCH)-containing neurons in the lateral hypothalamic area (LHA) are hypothesized to play an important role in hedonic feeding. A reciprocal connection between NAc MSNs and MCH-containing neurons is proposed to form a neuronal circuit that is involved in hedonic feeding. Although NAc MSNs have been shown to receive projection from MCH-containing neurons, it is not known whether MCH-containing neurons in the LHA also receive direct inputs from NAc MSNs. Here, we developed a genetic approach that allows us to visualize almost all striatal MSNs including NAc MSNs. We demonstrate that striatal MSNs terminate in a distinct region within the anterior LHA, and that the terminal area of striatal MSNs in this region contains glutamatergic neurons and is distinctly separate from orexin/hypocretin- or MCH-containing neurons. These observations suggest that NAc MSNs do not directly innervate MCH-containing neurons, but may indirectly signal MCH-containing neurons via glutamatergic neurons in the anterior LHA.
authors.affiliation: Molecular Neurogenetics Unit, Horizontal Medical Research Organization, Kyoto University Graduate School of Medicine, Kyoto 606-8501, Japan.
authors.forename: Hiromi
authors.initials: H
authors.lastname: Sano
authors.forename: Mineto
authors.initials: M
authors.lastname: Yokoi
mesh_terms: D000818:Animals; D003342:Corpus Striatum / Q000166:cytology / Q000378:metabolism*; D005247:Feeding Behavior / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics; D007026:Hypothalamic Area, Lateral / Q000166:cytology / Q000378:metabolism*; D007028:Hypothalamic Hormones / Q000378:metabolism*; D047908:Intracellular Signaling Peptides and Proteins / Q000378:metabolism*; D008543:Melanins / Q000378:metabolism*; D051379:Mice; D008822:Mice, Transgenic; D009433:Neural Inhibition / Q000502:physiology; D009434:Neural Pathways / Q000166:cytology / Q000378:metabolism*; D009474:Neurons / Q000378:metabolism*; D009479:Neuropeptides / Q000378:metabolism*; D000068797:Orexins; D010907:Pituitary Hormones / Q000378:metabolism*; D017729:Presynaptic Terminals / Q000378:metabolism / Q000648:ultrastructure; D012201:Reward; D009435:Synaptic Transmission / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D007028:Hypothalamic Hormones; D047908:Intracellular Signaling Peptides and Proteins; D008543:Melanins; D009479:Neuropeptides; D000068797:Orexins; D010907:Pituitary Hormones; D049452:Green Fluorescent Proteins; D005680:gamma-Aminobutyric Acid; C019463:melanin-concentrating hormone