Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P01189 (beta-endorphin)
 21,003 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

After synaptic release, glutamate is taken up by the nerve terminal via a plasma membrane-associated protein termed excitatory amino acid transporter 3 (EAAT3). Following entry into the nerve terminal, glutamate is pumped into synaptic vesicles by a vesicular transport system. Three different vesicular glutamate transporter proteins (VGLUT1-3) representing unique markers for glutamatergic neurons were recently characterized. The presence of EAAT3, glutaminase and VGLUT1-3 was examined in mouse, rat and rabbit species at mRNA and protein levels in hypothalamic neurons which are involved in the regulation of body weight using in situ hybridization and immunohistochemistry. EAAT3 and glutaminase mRNAs were demonstrated in all parts of the arcuate nucleus in the dorsomedial and ventromedial hypothalamic nuclei and lateral hypothalamic area. VGLUT1 mRNA was present in the magnocellular lateral hypothalamic nucleus. VGLUT2 mRNA was demonstrated in a subpopulation of neurons in the arcuate nucleus and in the ventromedial and dorsomedial hypothalamic nuclei and lateral hypothalamic area. Few VGLUT3 mRNA expressing neurons were scattered throughout the medial and lateral hypothalamus. EAAT3-like immunoreactivity (-li) was demonstrated in glutamate, neuropeptide Y (NPY), agouti-related peptide (AGRP), pro-opiomelanocortin (POMC), cocaine and amphetamine-regulated transcript (CART), melanin-concentrating hormone and orexin-immunoreactive (-ir) neurons. VGLUT2-li could only be demonstrated in POMC- and CART-ir neurons of the ventrolateral arcuate nucleus. The results show that key neurons involved in regulation of energy balance are glutamatergic and/or densely innervated by glutamatergic nerve terminals. Whereas orexigenic NPY/AGRP neurons situated in the ventromedial part of the arcuate nucleus are mainly GABAergic, it is shown that several anorexigenic POMC/CART neurons of the ventromedial arcuate nucleus are most likely glutamatergic [corrected].
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PMID:Plasma membrane and vesicular glutamate transporter mRNAs/proteins in hypothalamic neurons that regulate body weight. 1295 25

Glutamate plays a role in the central regulation of the hypothalamic-pituitary-adrenal (HPA) and thyroid (HPT) axes. Until the recent discovery of vesicular glutamate transporters (VGLUT1-3), there was no specific tool for the examination of the putative morphological relationship between the glutamatergic and the hypophysiotropic systems. Using antisera against VGLUT2, corticotropin-releasing hormone (CRH), and prothyrotropin-releasing hormone (proTRH) (178-199), we performed double-labeling immunocytochemistry at light and electron microscopic levels in order to study the glutamatergic innervation of the CRH- and TRH-synthesizing neurons in the hypothalamic paraventricular nucleus (PVN). Fine VGLUT2-immunoreactive (IR) axons very densely innervated the parvocellular subdivisions of the PVN. VGLUT2-IR axons established juxtapositions with all parvocellular CRH- and TRH-synthesizing neurons. The innervation was similarly intense in all parvocellular subdivisions of the PVN. At ultrastructural level, VGLUT2-IR terminals frequently established synapses with perikarya and dendrites of the CRH- and proTRH-IR neurons. These findings demonstrate that glutamatergic neurons directly innervate hypophysiotropic CRH and TRH neurons in the PVN and, therefore, support the hypothesis that the glutamate-induced activation of the HPA and HPT axes may be accomplished by a direct action of glutamate on hypophysiotropic CRH and TRH systems.
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PMID:Glutamatergic innervation of corticotropin-releasing hormone- and thyrotropin-releasing hormone-synthesizing neurons in the hypothalamic paraventricular nucleus of the rat. 1578 Oct 46

During the last two decades attention has been focussed on the role of different neuropeptides in hypothalamic control of feeding behavior. Several hypothalamic peptides that participate in the control of ingestive behavior are produced in neuronal cell bodies of the arcuate nucleus and/or the lateral hypothalamic area. Apart from producing orexigenic or anorexigenic compounds of peptidergic nature, these neurons also produce excitatory and inhibitory amino acid neurotransmitters. The role of GABA and glutamate in regulating energy balance has received less attention in comparison to neuropeptides. The arcuate nucleus-median eminence area, a region with a weak blood-brain barrier, contains at least two neuronal cell populations that exert opposing actions on energy balance. The majority of the neurons located in the ventromedial aspect of the arcuate nucleus, which produce the orexigenic peptides neuropeptide Y (NPY) and agouti-related peptide (AGRP), contain in addition the GABA-synthesizing enzyme glutamic acid decarboxylase (GAD) and the vesicular GABA transporter (VGAT), thereby supporting their GABAergic nature. Some neurons producing pro-opiomelanocortin (POMC)- and cocaine- and amphetamine-regulated transcript (CART), located in the ventrolateral division of the arcuate nucleus have recently been reported to contain the vesicular glutamate transporter 2 (VGLUT2), a marker for glutamatergic neurons, and the acetylcholine (ACh) synthesizing enzyme choline acetyltransferase (ChAT) as well as the vesicular ACh transporter (VAChT), supporting also a cholinergic phenotype. In the lateral hypothalamic area, hypocretin/orexin neurons express VGLUT1 or VGLUT2, but not GAD, whereas some melanin-concentrating hormone (MCH) cells contain GAD. These observations support the view that several classical transmitters, relatively neglected feeding transmitters candidates, are present in key neurons that regulate body weight and consequently may represent important orexigenic/anorexigenic mediators that convey information to other neurons within the hypothalamus as well as from the hypothalamus to other brain regions that participate in regulation of energy balance.
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PMID:Neurotransmitters in key neurons of the hypothalamus that regulate feeding behavior and body weight. 1758 36