Orexin neurons regulation

Yamanaka, A., Beuckmann, C. T., Willie, J. T. et al. (2003). Hypothalamic orexin neurons regulate arousal according to energy balance in mice. Neuron 38, 701-13. 

Bayer, L., Mairet-Coello, G., Risold, P. Y. 8r Griffond, B. (2002). Orexin/hypocretin neurons chemical phenotype and possible interactions with melanin-concentrating hormone neurons. Regul. Pept. 104, 33-9. 

Yamanaka A., Muraki Y., Ichiki K el al. (2006). Orexin neurons are directly and indirectly regulated by catecholamines in a complex manner. J. Neurophysiol. Epub-ahead of print. 

Yamanaka A., Muraki Y Tsujino N., Goto K., Sakurai T. (2003). Regulation of orexin neurons by the monoaminergic and cholinergic systems. Biochem. Biophys. Res. Commun. 303, 120-9. 

Lesions of the lateral hypothalamic area (LHA) cause anorexia, whereas ablation of the paraventricular nucleus (PVN) cause a hyperphagic obesity syndrome. Consistent with these results, LHA neurons express the orexigenic neuropeptides MCH and orexin. PVN neurons produce several neuropeptides that are anorex-igenic when administered directly into the brain (CRH, TRH, oxytocin), in addition to their better known roles as endocrine regulators. LHA and PVN receive rich inputs from axons of NPY/AgRP and aMSH/CART-producing neurons in the arcuate nucleus. 

Guan, J. L., Uehara, K., Lu, S. et at (2002). Reciprocal synaptic relationships between orexin- and melanin-concentrating hormone-containing neurons in the rat lateral hypothalamus a novel circuit implicated in feeding regulation. Int. J. Obes. Relat. Metab. Disord. 26, 1523-32. 

Davis SF, Williams KW, Xu W (2003) Selective enhancement of synaptic inhibition by hypocre-tin (orexin) in rat vagal motor neurons implications for autonomic regulation. J Neurosci 23 3844-54... 

Tu B, Timofeeva O, Jiao Y et al (2005) Spontaneous release of neuropeptide Y tonically inhibits recurrent mossy fiber synaptic transmission in epileptic brain. J Neurosci 25 1718-29 Ueda H, Fukushima N, Ge M et al (1987) Presynaptic opioid kappa-receptor and regulation of the release of Met-enkephalin in the rat brainstem. Neurosci Lett 81 309-13 van den Pol AN, Gao XB, Obrietan K et al (1998) Presynaptic and postsynaptic actions and modulation of neuroendocrine neurons by a new hypothalamic peptide, hypocretin/orexin. J Neurosci 18 7962-71... 

The neurons containing orexin/hypocretin are located in the dorsolateral and posterior hypothalamus and have widespread projections in the brain and in the spinal cord (Peyron et al., 1998), indicating that they may be involved in multiple functions (see the reviews by Kilduff and Peyron, 2000 Sutcliffe and de Lecea, 2002). In particular, the orexin/ hypocretin system has been implicated in neuroendocrine and autonomic functions, in addition to food intake regulation. The hypocretin/orexin peptides are excitatory. 

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