keyword
MENU ▼
Read by QxMD icon Read
search

nAChRs

keyword
https://www.readbyqxmd.com/read/28935799/interacting-amino-acid-replacements-allow-poison-frogs-to-evolve-epibatidine-resistance
#1
Rebecca D Tarvin, Cecilia M Borghese, Wiebke Sachs, Juan C Santos, Ying Lu, Lauren A O'Connell, David C Cannatella, R Adron Harris, Harold H Zakon
Animals that wield toxins face self-intoxication. Poison frogs have a diverse arsenal of defensive alkaloids that target the nervous system. Among them is epibatidine, a nicotinic acetylcholine receptor (nAChR) agonist that is lethal at microgram doses. Epibatidine shares a highly conserved binding site with acetylcholine, making it difficult to evolve resistance yet maintain nAChR function. Electrophysiological assays of human and frog nAChR revealed that one amino acid replacement, which evolved three times in poison frogs, decreased epibatidine sensitivity but at a cost of acetylcholine sensitivity...
September 22, 2017: Science
https://www.readbyqxmd.com/read/28932225/expression-and-function-of-the-cholinergic-system-in-immune-cells
#2
REVIEW
Takeshi Fujii, Masato Mashimo, Yasuhiro Moriwaki, Hidemi Misawa, Shiro Ono, Kazuhide Horiguchi, Koichiro Kawashima
T and B cells express most cholinergic system components-e.g., acetylcholine (ACh), choline acetyltransferase (ChAT), acetylcholinesterase, and both muscarinic and nicotinic ACh receptors (mAChRs and nAChRs, respectively). Using ChAT(BAC)-eGFP transgenic mice, ChAT expression has been confirmed in T and B cells, dendritic cells, and macrophages. Moreover, T cell activation via T-cell receptor/CD3-mediated pathways upregulates ChAT mRNA expression and ACh synthesis, suggesting that this lymphocytic cholinergic system contributes to the regulation of immune function...
2017: Frontiers in Immunology
https://www.readbyqxmd.com/read/28928637/alpha7-nicotinic-acetylcholine-receptors-play-a-predominant-role-in-the-cholinergic-potentiation-of-n-methyl-d-aspartate-evoked-firing-responses-of-hippocampal-ca1-pyramidal-cells
#3
Zsolt K Bali, Lili V Nagy, István Hernádi
The aim of the present study was to identify in vivo electrophysiological correlates of the interaction between cholinergic and glutamatergic neurotransmission underlying memory. Extracellular spike recordings were performed in the hippocampal CA1 region of anesthetized rats in combination with local microiontophoretic administration of N-methyl-D-aspartate (NMDA) and acetylcholine (ACh). Both NMDA and ACh increased the firing rate of the neurons. Furthermore, the simultaneous delivery of NMDA and ACh resulted in a more pronounced excitatory effect that was superadditive over the sum of the two mono-treatment effects and that was explained by cholinergic potentiation of glutamatergic neurotransmission...
2017: Frontiers in Cellular Neuroscience
https://www.readbyqxmd.com/read/28928157/alteration-of-cholinergic-anti-inflammatory-pathway-in-rat-with-ischemic-cardiomyopathy-modified-electrophysiological-function-of-heart
#4
Shu-Jie Wu, Yue-Chun Li, Zhe-Wei Shi, Zhong-Hao Lin, Zhi-Heng Rao, Si-Chao Tai, Mao-Ping Chu, Lei Li, Jia-Feng Lin
BACKGROUND: With chronic ischemia after myocardial infarction, the resulting scar tissue result in electrical and structural remodeling vulnerable to an arrhythmogenic substrate. The cholinergic anti-inflammatory pathway elicited by vagal nerve via α7 nicotinic acetylcholine receptors (α7-nAChR) can modulate local and systemic inflammatory responses. Here, we aimed to clarify a novel mechanism for the antiarrhythmogenic properties of vagal nerve during the ischemic cardiomyopathy (ICM)...
September 19, 2017: Journal of the American Heart Association
https://www.readbyqxmd.com/read/28917942/in-vivo-and-in-vitro-testing-of-native-%C3%AE-conotoxins-from-the-injected-venom-of-conus-purpurascens
#5
REVIEW
Mickelene F Hoggard, Alena M Rodriguez, Herminsul Cano, Evan Clark, Han-Shen Tae, David J Adams, Tanja A Godenschwege, Frank Marí
α-Conotoxins inhibit nicotinic acetylcholine receptors (nAChRs) and are used as probes to study cholinergic pathways in vertebrates. Model organisms, such as Drosophila melanogaster, express nAChRs in their CNS that are suitable to investigate the neuropharmacology of α-conotoxins in vivo. Here we report the paired nanoinjection of native α-conotoxin PIA and two novel α-conotoxins, PIC and PIC[O7], from the injected venom of Conus purpurascens and electrophysiological recordings of their effects on the giant fiber system (GFS) of D...
September 13, 2017: Neuropharmacology
https://www.readbyqxmd.com/read/28912862/astragalus-polysaccharides-combined-with-ibuprofen-exhibit-a-therapeutic-effect-on-septic-rats-via-an-anti-inflammatory-cholinergic-pathway
#6
Li Liu, Shibiao Chen, Xiaoyun Xu, Benchao Hou, Fei Mo
The aim of the present study was to investigate the effects of Astragalus polysaccharides (APS) in combination with ibuprofen (IBU) in the treatment of sepsis and the underlying mechanism. The combined drug treatment was evaluated in a rat model of cecal ligation and puncture (CLP). The serum concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6 and acetylcholine (ACh) were determined. Nicotinic acetylcholine (nAChR) α7 receptor expression and histopathological changes in the lung tissue were also observed...
October 2017: Experimental and Therapeutic Medicine
https://www.readbyqxmd.com/read/28911734/both-point-mutations-and-low-expression-levels-of-the-nicotinic-acetylcholine-receptor-%C3%AE-1-subunit-are-associated-with-imidacloprid-resistance-in-an-aphis-gossypii-glover-population-from-a-bt-cotton-field-in-china
#7
Xuewei Chen, Fen Li, Anqi Chen, Kangsheng Ma, Pingzhuo Liang, Ying Liu, Dunlun Song, Xiwu Gao
Aphis gossypii Glover is a destructive pest of numerous crops throughout the world. Although the expansion of Bt cotton cultivation has helped to control some insect pests, the damage from cotton aphids has not been mitigated. The evolution of aphid resistance to imidacloprid has made its chemical control more difficult since its introduction in 1991. Field populations of A. gossypii that were collected from different transgenic (Bt) cotton planting areas of China in 2014 developed different levels of resistance to imidacloprid...
September 2017: Pesticide Biochemistry and Physiology
https://www.readbyqxmd.com/read/28906438/acetylcholinesterase-and-nicotinic-acetylcholine-receptors-in-schistosomes-and-other-parasitic-helminths
#8
REVIEW
Hong You, Chang Liu, Xiaofeng Du, Donald P McManus
Schistosomiasis, which is caused by helminth trematode blood flukes of the genus Schistosoma, is a serious health and economic problem in tropical areas, and the second most prevalent parasitic disease after malaria. Currently, there is no effective vaccine available and treatment is entirely dependent on a single drug, praziquantel (PZQ), raising a significant potential public health threat due to the emergence of PZQ drug resistance. It is thus urgent and necessary to explore novel therapeutic targets for the treatment of schistosomiasis...
September 14, 2017: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
https://www.readbyqxmd.com/read/28904864/a-g-protein-coupled-%C3%AE-7-nicotinic-receptor-regulates-signaling-and-tnf-%C3%AE-release-in-microglia
#9
Justin R King, Trudy C Gillevet, Nadine Kabbani
Acetylcholine activation of α7 nicotinic acetylcholine receptors (α7 nAChRs) in microglia attenuates neuroinflammation and regulates TNF-α release. We used lipopolysaccharide to model inflammation in the microglial cell line EOC20 and examined signaling by the α7 nAChR. Co-immunoprecipitation experiments confirm that α7 nAChRs bind heterotrimeric G proteins in EOC20 cells. Interaction with Gαi mediates α7 nAChR signaling via enhanced intracellular calcium release and a decrease in cAMP, p38 phosphorylation, and TNF-α release...
September 2017: FEBS Open Bio
https://www.readbyqxmd.com/read/28901722/%C3%AE-6-subunit-containing-nicotinic-receptors-mediate-low-dose-ethanol-effects-on-ventral-tegmental-area-neurons-and-ethanol-reward
#10
Scott C Steffensen, Samuel I Shin, Ashley C Nelson, Stephanie S Pistorius, Stephanie B Williams, Taylor J Woodward, Hyun Jung Park, Lindsey Friend, Ming Gao, Fenfei Gao, Devin H Taylor, M Foster Olive, Jeffrey G Edwards, Sterling N Sudweeks, Lori M Buhlman, J Michael McIntosh, Jie Wu
Dopamine (DA) neuron excitability is regulated by inhibitory GABAergic synaptic transmission and modulated by nicotinic acetylcholine receptors (nAChRs). The aim of this study was to evaluate the role of α6 subunit-containing nAChRs (α6*-nAChRs) in acute ethanol effects on ventral tegmental area (VTA) GABA and DA neurons. α6*-nAChRs were visualized on GABA terminals on VTA GABA neurons, and α6*-nAChR transcripts were expressed in most DA neurons, but only a minority of VTA GABA neurons from GAD67 GFP mice...
September 13, 2017: Addiction Biology
https://www.readbyqxmd.com/read/28901280/neuronal-and-extraneuronal-nicotinic-acetylcholine-receptors
#11
Michele Zoli, Susanna Pucci, Antonietta Vilella, Cecilia Gotti
Neuronal nicotinic acetylcholine receptors (nAChRs) belong to a super-family of Cys-loop ligand-gated ion channels that respond to endogenous acetylcholine (ACh) or other cholinergic ligands. These receptors are also the targets of drugs such as nicotine (the main addictive agent delivered by cigarette smoke) and are involved in a variety of physiological and pathophysiological processes. Numerous studies have shown that the expression and/or function of nAChRs is compromised in many neurological and psychiatric diseases...
September 11, 2017: Current Neuropharmacology
https://www.readbyqxmd.com/read/28891599/expression-in-e-coli-of-fusion-protein-comprising-%C3%AE-conotoxin-txib-and-preservation-of-selectivity-to-nicotinic-acetylcholine-receptors-in-the-purified-product
#12
Jinpeng Yu, Xiaopeng Zhu, Yang Yang, Sulan Luo, Dongting Zhangsun
Nicotinic acetylcholine receptors (nAChRs) are ligand-gated ion channels, which are widely distributed in the central and peripheral nervous system. The α6β2* nAChR is an important subtype, which is closely associated with nicotine addiction and movement disorders etc. α-Conotoxin TxIB with 16-amino acid residues specifically targets α6β2* nAChR with no obvious effect on other nAChR subtypes. However, chemical synthesis of TxIB is expensive and the quantity of native TxIB extracted from cone snail is limited...
September 11, 2017: Chemical Biology & Drug Design
https://www.readbyqxmd.com/read/28885019/sulfonium-as-a-surrogate-for-ammonium-a-new-%C3%AE-7-nicotinic-acetylcholine-receptor-partial-agonist-with-desensitizing-activity
#13
Marta Quadri, Clare Stokes, Alican Gulsevin, Ashley C J Felts, Khalil A Abboud, Roger L Papke, Nicole A Horenstein
Weak partial agonists that promote a desensitized state of the α7 nicotinic acetylcholine receptor (nAChR) have been associated with anti-inflammatory effects. Exemplar compounds feature a tertiary or quaternary ammonium group. We report the synthesis, structure, and electrophysiological evaluation of 1-ethyl-4-phenylthiomorpholin-1-ium triflate, a weak partial agonist with a sulfonium isostere of the ammonium pharmacophore. These results offer new insights in understanding nAChR-ligand interactions and provide a new chemical space to target the α7 nAChR...
September 8, 2017: Journal of Medicinal Chemistry
https://www.readbyqxmd.com/read/28878681/alpha5-nicotinic-acetylcholine-receptor-contributes-to-nicotine-induced-lung-cancer-development-and-progression
#14
Hai-Ji Sun, Yan-Fei Jia, Xiao-Li Ma
Nicotine and nicotinic acetylcholine receptors (nAChRs) are considered to be involved in lung cancer risk, onset and progression, but their precise physiological roles in these contexts remain unclear. Our previous studies suggested that α5-nAChR mediates nicotine-induced lung cancer cell proliferation, migration, and invasion in vitro. In this study, we aimed to determine the role of α5-nAChR in the development and progression of non-small cell lung cancer (NSCLC). Our microarray results reveal that knockdown of the CHRNA5 gene encoding α5-nAChR significantly modulates key pathways including the cell cycle, DNA replication, pathway in cancer...
2017: Frontiers in Pharmacology
https://www.readbyqxmd.com/read/28878016/enantiomeric-barbiturates-bind-distinct-inter-and-intra-subunit-binding-sites-in-a-nicotinic-acetylcholine-receptor-nachr
#15
Zhiyi Yu, Jonathan B Cohen
Nicotinic acetylcholine receptors (nAChRs) and γ-aminobutyric acid type A receptors (GABAARs) are members of the pentameric ligand-gated ion channel superfamily. Drugs acting as positive allosteric modulators of muscle-type α2βγδ nAChRs, of use in treatment of neuromuscular disorders, have been hard to identify. However, identification of nAChR allosteric modulator binding sites has been facilitated by using drugs developed as photoreactive GABAAR modulators. Recently, R-mTFD-MPAB (R-1-methyl-5-allyl-5-(m-trifluoromethyl-diazirinylphenyl) barbituric acid), an anesthetic and GABAAR potentiator, has been shown to inhibit Torpedo α2βγδ nAChRs, binding in the ion channel and to a γ(+)-α(-) subunit interface site similar to its GABAAR intersubunit binding site...
September 6, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28875553/human-brain-imaging-of-nicotinic-acetylcholine-%C3%AE-4%C3%AE-2-receptors-using-18-f-nifene-selectivity-functional-activity-toxicity-aging-effects-gender-effects-and-extrathalamic-pathways
#16
Jogeshwar Mukherjee, Patrick J Lao, Tobey J Betthauser, Gurleen K Samra, Min-Liang Pan, Ishani H Patel, Christopher Liang, Raju Metherate, Bradley T Christian
Nicotinic acetylcholinergic receptors (nAChR's) have been implicated in several brain disorders, including addiction, Parkinson's disease, Alzheimer's disease and schizophrenia. Here we report in vitro selectivity and functional properties, toxicity in rats, in vivo evaluation in humans, and comparison across species of [(18) F]Nifene, a fast acting PET imaging agent for α4β2* nAChRs. Nifene had subnanomolar affinities for hα2β2 (0.34 nM), hα3β2 (0.80 nM) and hα4β2 (0.83 nM) nAChR but weaker (27 to 219 nM) for hβ4 nAChR subtypes and 169 nM for hα7 nAChR...
September 5, 2017: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/28874590/discovery-of-peptide-ligands-through-docking-and-virtual-screening-at-nicotinic-acetylcholine-receptor-homology-models
#17
Abba E Leffler, Alexander Kuryatov, Henry A Zebroski, Susan R Powell, Petr Filipenko, Adel K Hussein, Juliette Gorson, Anna Heizmann, Sergey Lyskov, Richard W Tsien, Sébastien F Poget, Annette Nicke, Jon Lindstrom, Bernardo Rudy, Richard Bonneau, Mandë Holford
Venom peptide toxins such as conotoxins play a critical role in the characterization of nicotinic acetylcholine receptor (nAChR) structure and function and have potential as nervous system therapeutics as well. However, the lack of solved structures of conotoxins bound to nAChRs and the large size of these peptides are barriers to their computational docking and design. We addressed these challenges in the context of the α4β2 nAChR, a widespread ligand-gated ion channel in the brain and a target for nicotine addiction therapy, and the 19-residue conotoxin α-GID that antagonizes it...
September 5, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28867753/the-%C3%AE-7-nicotinic-acetylcholine-receptor-positive-allosteric-modulator-attenuates-lipopolysaccharide-induced-activation-of-hippocampal-i%C3%AE%C2%BAb-and-cd11b-gene-expression-in-mice
#18
Muzaffar Abbas, Sami Alzarea, Roger L Papke, Shafiqur Rahman
We have reported that 3a,4,5,9b-tetrahydro-4-(1-naphthalenyl)-3H-cyclopentan[c]quinoline-8-sulfonamide (TQS), α7 nicotinic acetylcholine receptor (nAChR) positive allosteric modulator (PAM) reduces lipopolysaccharide (LPS)-induced hyperalgesia and allodynia in mice. The objective of the present study was to determine the effects of TQS on LPS-induced activation of hippocampal inhibitor of κB (IκB) and cluster of differentiation 11b (CD11b) gene expression involving hyperalgesia and allodynia in mice. We also examined the effects of TQS on microglial phenotype following LPS administration...
2017: Drug Discoveries & Therapeutics
https://www.readbyqxmd.com/read/28863823/the-role-of-cholesterol-in-the-activation-of-nicotinic-acetylcholine-receptors
#19
John E Baenziger, Jaimee A Domville, J P Daniel Therien
Cholesterol is a potent modulator of the nicotinic acetylcholine receptor (nAChR) from Torpedo. Here, we review current understanding of the mechanisms underlying cholesterol-nAChR interactions in the context of increasingly available high-resolution structural and functional data. Cholesterol and other lipids influence function by conformational selection and kinetic mechanisms, stabilizing varying proportions of activatable vs nonactivatable conformations, as well as influencing the rates of transitions between conformational states...
2017: Current Topics in Membranes
https://www.readbyqxmd.com/read/28863815/direct-interactions-of-cholesterol-with-pentameric-ligand-gated-ion-channels-testable-hypotheses-from-computational-predictions
#20
Grace Brannigan
Several essential ionotropic neurotransmitter receptors, including the nicotinic acetylcholine receptor (nAChR) and gamma-aminobutyric acid (GABA) type A receptor (GABAAr), belong to the family of pentameric ligand-gated ion channels (pLGICs). Function of these receptors is particularly sensitive to their lipid environment, including cholesterol and cholesterol-derived neurosteroids. Direct structural data investigating interactions between sterols and pLGICs, as well as their role in modulatory mechanisms, are largely unavailable...
2017: Current Topics in Membranes
keyword
keyword
41099
1
2
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read
×

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"