Aspartate receptors

The main interaction with the receptor has been proposed [37] and later confirmed [38] to occur through a charge-reinforced H-bond between an anionic site in the receptor (aspartate ion on the 3 transmembrane a-helix) and the protonated quinazoline N. ... 

NMD A receptors are selectively activated by A/-methyl-D-aspartate (NMD A) (182). NMD A receptor activation also requires glycine or other co-agonist occupation of an allosteric site. NMDAR-1, -2A, -2B, -2C, and -2D are the five NMD A receptor subunits known. Two forms of NMDAR-1 are generated by alternative splicing. NMDAR-1 proteins form homomeric ionotropic receptors in expression systems and may do so m situ in the CNS. Functional responses, however, are markedly augmented by co-expression of a NMDAR-2 and NMDAR-1 subunits. The kinetic and pharmacological properties of the NMD A receptor are influenced by the particular subunit composition. 

The existence of protein receptors in the tongues of mice and cows have been shown. Monosodium L-glutamate MSG [142-47-2] is utilized as a food flavor enhancer in various seasonings and processed foods. D-Glutamate is tasteless. L-Aspartic acid salt has a weaker taste of umami. Glycine and L-alanine are slightly sweet. The relationship between taste and amino acid stmcture has been discussed (222). 

Compounds that have agonistic properties at glutamate or aspartate receptors are also CNS stimulants, readily cause convulsions, and presumably could also be employed as analeptics. Three separate excitatory amino acid receptor subtypes have been characterized pharmacologically, based on the relative potency of synthetic agonists. These three receptors are named for their respective prototypical agonists A/-methyl-D-aspartate [6384-92-5]... 

Grb-2 facilitates the transduction of an extracellular stimulus to an intracellular signaling pathway, (b) The adaptor protein PSD-95 associates through one of its three PDZ domains with the N-methyl-D-aspartic acid (NMDA) receptor. Another PDZ domain associates with a PDZ domain from neuronal nitric oxide synthase (nNOS). Through its interaction with PSD-95, nNOS is localized to the NMDA receptor. Stimulation by glutamate induces an influx of calcium, which activates nNOS, resulting in the production of nitric oxide. 

Long-term potentiation (LTP) is a synaptic plasticity phenomenon that corresponds to an increase in the synaptic strength (increase in the post-synaptic response observed for the same stimulation of the presynaptic terminals) observed after a high frequency stimulation (tetanus) of the afferent fibres. This increased response is still observed hours and even days after the tetanus. The phenomenon is often observed at glutamatergic synapses and involves, in most cases, the activation of the V-methyl D-aspartate (NMDA) subtype of ionotropic glutamate receptors. 

NMDA (iV-methyl-D-aspartic acid) is a synthetic derivative of aspartic acid and represents the prototypical agonist at the NMDA receptors for which the latter were named. 

On the pathophysiological side, hyperactive nNOS has been implicated in A/-methyl-D-aspartate (NMDA)-receptor-mediated neuronal death in cerebrovascular-stroke. Some disturbances of smooth muscle tone within the gastrointestinal tract (e.g., gastroesophageal reflux disease) may also be related to an overproduction of NO by nNOS in peripheral nitrergic nerves. 

Mesolimbic System/Reward System Metabolic Syndrome Metabotropic Glutamate Receptors Metabotropic Receptor Metalloprote(in)ases Methicillin-resistant Staphylococci iV-Methyl D-aspartate Receptors Methylating Agents... 

Krystal JH, Petrakis IL, Mason G, et al V-methyl-D-aspartate glutamate receptors and alcoholism reward, dependence, treatment, and vulnerability. Pharmacol Ther 99 79-94, 2003b... 

Cruz SE, Mirshahi T, Thomas B, et al Effects of the abused solvent toluene on recombinant N-methyl-D-aspartate and non-N-methyl-D-aspartate receptors expressed in Xenopus oocytes. J Pharmacol Exp Ther 286 334-340, 1998 De Rosa E, Bartolucci GB, Sigon M, et al Hippuric acid and ortho-cresol as biological indicators ofoccupational exposure to toluene. Am J Ind Med 11 529—537,1987 Delteil P, Stoesser F, Stoesser R L theromanie. Ann Med Psychol (Paris) 1 329-340, 1974... 

These include nicotinic acetylcholine receptors, neuronal calcium channels, muscle sodium channels, vasopressin receptors, and iV-methyl-D-aspartate (NMDA) receptors. Some general features of the structure, function, and evolution of biologically active peptides isolated from Conus venom are presented. 

Some derivatives of adamantane with antagonist or agonist effects have also been synthesized. For instance, monocationic and dicationic adamantane derivatives block the a-amino-3-hydroxy-5-methylisoxazole -propionic acid (AMPA) receptors, A-methyl-o-aspartate (NMDA) receptors [134—136] and 5-hydroxytryptamine (5-HT3) receptors [137]. 

NMDAR. A-methyl-D-aspartate receptor—an ionotropic receptor for glutamate. It plays a critical role in synaptic plasticity mechanisms and thus is necessary for several types of learning and memory. 

Mechanisms of HIV-Induced Neurodegeneration Roles for Excitotoxins and N-Methyl-o-Aspartate Receptors... 

Bachis A, Mocchetti I (2004) The chemokine receptor CXCR4 and not the N-methyl-D-aspartate receptor mediates gpl20 neurotoxicity in cerebellar granule cells. J Neurosci Res 75(1) 75-82... 

Lynch DR, Guttmann RP (2002) Excitotoxicity perspectives based on N-methyl-D-aspartate receptor subtypes. J Pharmacol Exp Ther 300(3) 717-723 Magnuson DS, Knudsen BE, Geiger JD, Brownstone RM, Nath A (1995) Human immunodeficiency virus type 1 tat activates non-N-methyl-D-aspartate excitatory amino acid receptors and causes neurotoxicity. Ann Neurol 37(3) 373-380 Mamdouh Z, Chen X, Kerini LM, Maxfield FR, Muller WA (2003) Targeted recycling of PECAM from endothelial surface-connected compartments during diapedesis. Nature 421(6924) 748-753... 

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