keyword
MENU ▼
Read by QxMD icon Read
search

Nav channels

keyword
https://www.readbyqxmd.com/read/28542706/modulatory-features-of-the-novel-spider-toxin-%C3%AE-trtx-df1a-isolated-from-the-venom-of-the-spider-davus-fasciatus
#1
Fernanda C Cardoso, Zoltan Dekan, Jennifer J Smith, Jennifer R Deuis, Irina Vetter, Volker Herzig, Paul F Alewood, Glenn F King, Richard J Lewis
BACKGROUND AND PURPOSE: Naturally occurring dysfunction in NaV channels results in complex disorders such as chronic pain, making these channels an attractive target for new therapies. In the pursuit of novel NaV modulators, we investigated spider venoms for new inhibitors of NaV channels. EXPERIMENTAL APPROACH: We used high-throughput screens to identify a NaV modulator in venom of the spider Davus fasciatus. Further characterization of this venom peptide was undertaken using fluorescent and electrophysiological assays, molecular modeling and a rodent pain model...
May 24, 2017: British Journal of Pharmacology
https://www.readbyqxmd.com/read/28534438/the-axonal-cytoskeleton-and-the-assembly-of-nodes-of-ranvier
#2
Aniket Ghosh, Diane L Sherman, Peter J Brophy
Vertebrate nervous systems rely on rapid nerve impulse transmission to support their complex functions. Fast conduction depends on ensheathment of nerve axons by myelin-forming glia and the clustering of high concentrations of voltage-gated sodium channels (Nav) in the axonal gaps between myelinated segments. These gaps are the nodes of Ranvier. Depolarization of the axonal membrane initiates the action potential responsible for impulse transmission, and the Nav help ensure that this is restricted to nodes...
May 1, 2017: Neuroscientist: a Review Journal Bringing Neurobiology, Neurology and Psychiatry
https://www.readbyqxmd.com/read/28530638/sodium-channel-nav1-9-mutations-associated-with-insensitivity-to-pain-dampen-neuronal-excitability
#3
Jianying Huang, Carlos G Vanoye, Alison Cutts, Y Paul Goldberg, Sulayman D Dib-Hajj, Charles J Cohen, Stephen G Waxman, Alfred L George
Voltage-gated sodium channel (NaV) mutations cause genetic pain disorders that range from severe paroxysmal pain to a congenital inability to sense pain. Previous studies on NaV1.7 and NaV1.8 established clear relationships between perturbations in channel function and divergent clinical phenotypes. By contrast, studies of NaV1.9 mutations have not revealed a clear relationship of channel dysfunction with the associated and contrasting clinical phenotypes. Here, we have elucidated the functional consequences of a NaV1...
May 22, 2017: Journal of Clinical Investigation
https://www.readbyqxmd.com/read/28522250/ppargamma-agonists-rescue-increased-phosphorylation-of-fgf14-at-s226-in-the-tg2576-mouse-model-of-alzheimer-s-disease
#4
Wei-Chun J Hsu, Norelle C Wildburger, Sigmund J Haidacher, Miroslav N Nenov, Oluwarotimi Folorunso, Aditya K Singh, Brent C Chesson, Whitney F Franklin, Ibdanelo Cortez, Rovshan G Sadygov, Kelly T Dineley, Jay S Rudra, Giulio Taglialatela, Cheryl F Lichti, Larry Denner, Fernanda Laezza
BACKGROUND: Cognitive impairment in humans with Alzheimer's disease (AD) and in animal models of Aβ-pathology can be ameliorated by treatments with the nuclear receptor peroxisome proliferator-activated receptor-gamma (PPARγ) agonists, such as rosiglitazone (RSG). Previously, we demonstrated that in the Tg2576 animal model of AD, RSG treatment rescued cognitive deficits and reduced aberrant activity of granule neurons in the dentate gyrus (DG), an area critical for memory formation...
May 15, 2017: Experimental Neurology
https://www.readbyqxmd.com/read/28522215/blocking-voltage-gated-sodium-channels-as-a-strategy-to-suppress-pathological-cough
#5
REVIEW
Hui Sun, Marian Kollarik, Bradley J Undem
Pathological cough is thought to be secondary to inappropriate activation of vagal sensory nerves. Sensory nerves can be activated by a large number of disparate stimuli. The most relevant stimuli to block for effective anti-tussive therapy likely depend on the specific underlying pathology that is leading to the coughing. Blocking voltage-gated sodium channels (NaV) will prevent action potential initiation and conduction and therefore prevent sensory communication between the airways and brainstem. In so doing, they would be expected to inhibit evoked cough independently of the nature of the stimulus and underlying pathology...
May 15, 2017: Pulmonary Pharmacology & Therapeutics
https://www.readbyqxmd.com/read/28503166/inhibition-of-ectopic-arginine-vasopressin-production-by-phenytoin-in-the-small-cell-lung-cancer-cell-line-lu-165
#6
Takahiro Ohta, Mitsuo Mita, Shigeru Hishinuma, Reiko Ishii-Nozawa, Kazuhisa Takahashi, Masaru Shoji
Phenytoin, a voltage-gated sodium channel (NaV channel) antagonist, reportedly inhibits arginine vasopressin (AVP) release from an isolated rat neurohypophysis. So far, it is uncertain whether phenytoin has a direct action on ectopic AVP-producing neuroendocrine tumors. We studied the effect of phenytoin on the release of copeptin, the C-terminal fragment of pro-AVP, and expression of AVP gene in the human small cell lung cancer cell line Lu-165. Cells were maintained in RPMI1640 medium with 10% fetal bovine serum and were used within the fifth passage...
2017: Frontiers in Endocrinology
https://www.readbyqxmd.com/read/28497266/an-insecticidal-toxin-from-nephila-clavata-spider-venom
#7
Lin Jin, Mingqian Fang, Mengrou Chen, Chunling Zhou, Rose Ombati, Md Abdul Hakim, Guoxiang Mo, Ren Lai, Xiuwen Yan, Yumin Wang, Shilong Yang
Spiders are the most successful insect predators given that they use their venom containing insecticidal peptides as biochemical weapons for preying. Due to the high specificity and potency of peptidic toxins, discoveries of insecticidal toxins from spider venom have provided an opportunity to obtain natural compounds for agricultural applications without affecting human health. In this study, a novel insecticidal toxin (μ-NPTX-Nc1a) was identified and characterized from the venom of Nephila clavata. Its primary sequence is GCNPDCTGIQCGWPRCPGGQNPVMDKCVSCCPFCPPKSAQG which was determined by automated Edman degradation, cDNA cloning, and MS/MS analysis...
May 11, 2017: Amino Acids
https://www.readbyqxmd.com/read/28481659/ion-channel-mechanisms-underlying-frequency-firing-patterns-of-the-avian-nucleus-magnocellularis-a-computational-model
#8
Ting Lu, Kirstie Wade, Hui Hong, Jason Tait Sanchez
We have previously shown that late-developing avian nucleus magnocellularis (NM) neurons (embryonic [E] days 19-21) fire action potentials (APs) that resembles a band-pass filter in response to sinusoidal current injections of varying frequencies. NM neurons located in the mid- to high-frequency regions of the nucleus fire preferentially at 75 Hz, but only fire a single onset AP to frequency inputs greater than 200 Hz. Surprisingly, NM neurons do not fire APs to sinusoidal inputs less than 20 Hz regardless of the strength of the current injection...
May 8, 2017: Channels
https://www.readbyqxmd.com/read/28475112/insect-active-toxins-with-promiscuous-pharmacology-from-the-african-theraphosid-spider-monocentropus-balfouri
#9
Jennifer J Smith, Volker Herzig, Maria P Ikonomopoulou, Sławomir Dziemborowicz, Frank Bosmans, Graham M Nicholson, Glenn F King
Many chemical insecticides are becoming less efficacious due to rising resistance in pest species, which has created much interest in the development of new, eco-friendly bioinsecticides. Since insects are the primary prey of most spiders, their venoms are a rich source of insect-active peptides that can be used as leads for new bioinsecticides or as tools to study molecular receptors that are insecticidal targets. In the present study, we isolated two insecticidal peptides, µ/ω-TRTX-Mb1a and -Mb1b, from venom of the African tarantula Monocentropus balfouri...
May 5, 2017: Toxins
https://www.readbyqxmd.com/read/28473457/pharmacologic-characterization-of-amg8379-a-potent-and-selective-small-molecule-sulfonamide-antagonist-of-the-voltage-gated-sodium-channel-nav1-7
#10
Thomas J Kornecook, Ruoyuan Yin, Stephen Altmann, Xuhai Be, Virginia Berry, Christopher P Ilch, Michael Jarosh, Danielle Johnson, Josie H Lee, Sonya G Lehto, Joseph Ligutti, Dong Liu, Jason Luther, David Matson, Danny Ortuno, John Roberts, Kristin Taborn, Jinti Wang, Matthew M Weiss, Violeta Yu, Dawn X D Zhu, Robert T Fremeau, Bryan D Moyer
Potent and selective antagonists of the voltage-gated sodium channel NaV1.7 represent a promising avenue for the development of new chronic pain therapies. We generated a small molecule atropisomer quinolone sulfonamide antagonist AMG8379 and a less active enantiomer AMG8380. Here we show that AMG8379 potently blocks human NaV1.7 channels with an IC50 of 8.5 nM and endogenous tetrodotoxin (TTX)-sensitive sodium channels in dorsal root ganglia (DRG) neurons with an IC50 of 3.1 nM in whole cell patch clamp electrophysiology assays using a voltage protocol that interrogates channels in a partially inactivated state...
May 4, 2017: Journal of Pharmacology and Experimental Therapeutics
https://www.readbyqxmd.com/read/28469558/intracellular-fibroblast-growth-factor-14-emerging-risk-factor-for-brain-disorders
#11
REVIEW
Jessica Di Re, Paul A Wadsworth, Fernanda Laezza
The finely tuned regulation of neuronal firing relies on the integrity of ion channel macromolecular complexes. Minimal disturbances of these tightly regulated networks can lead to persistent maladaptive plasticity of brain circuitry. The intracellular fibroblast growth factor 14 (FGF14) belongs to the nexus of proteins interacting with voltage-gated Na+ (Nav) channels at the axonal initial segment. Through isoform-specific interactions with the intracellular C-terminal tail of neuronal Nav channels (Nav1.1, Nav1...
2017: Frontiers in Cellular Neuroscience
https://www.readbyqxmd.com/read/28450535/sodium-channel-nav1-8-underlies-ttx-resistant-axonal-action-potential-conduction-in-somatosensory-c-fibers-of-distal-cutaneous-nerves
#12
Amanda H Klein, Alina Vyshnevska, Timothy V Hartke, Roberto De Col, Joseph L Mankowski, Brian Turnquist, Frank Bosmans, Peter W Reeh, Martin Schmelz, Richard W Carr, Matthias Ringkamp
Voltage-gated sodium (NaV) channels are responsible for the initiation and conduction of action potentials within primary afferents. The nine NaV channel isoforms recognized in mammals are often functionally divided into tetrodotoxin (TTX)-sensitive (TTX-s) channels (NaV1.1-NaV1.4, NaV1.6-NaV1.7) that are blocked by nanomolar concentrations and TTX-resistant (TTX-r) channels (NaV1.8 and NaV1.9) inhibited by millimolar concentrations, with NaV1.5 having an intermediate toxin sensitivity. For small-diameter primary afferent neurons, it is unclear to what extent different NaV channel isoforms are distributed along the peripheral and central branches of their bifurcated axons...
May 17, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/28440808/automated-and-manual-patch-clamp-data-of-human-induced-pluripotent-stem-cell-derived-dopaminergic-neurons
#13
Denise Franz, Hervør Lykke Olsen, Oliver Klink, Jan Gimsa
Human induced pluripotent stem cells can be differentiated into dopaminergic neurons (Dopa.4U). Dopa.4U neurons expressed voltage-gated NaV and KV channels and showed neuron-like spontaneous electrical activity. In automated patch clamp measurements with suspended Dopa.4U neurons, delayed rectifier K(+) current (delayed KV) and rapidly inactivating A-type K(+) current (fast KV) were identified. Examination of the fast KV current with inhibitors yielded IC50 values of 0.4 mM (4-aminopyridine) and 0.1 mM (tetraethylammonium)...
April 25, 2017: Scientific Data
https://www.readbyqxmd.com/read/28428622/inhibition-of-late-sodium-current-suppresses-calcium-related-ventricular-arrhythmias-by-reducing-the-phosphorylation-of-camk-ii-and-sodium-channel-expressions
#14
Xiao-Hong Wei, Shan-Dong Yu, Lu Ren, Si-Hui Huang, Qiao-Mei Yang, Ping Wang, Yan-Peng Chu, Wei Yang, Yan-Sheng Ding, Yong Huo, Lin Wu
Cardiac arrhythmias associated with intracellular calcium inhomeostasis are refractory to antiarrhythmic therapy. We hypothesized that late sodium current (I Na) contributed to the calcium-related arrhythmias. Monophasic action potential duration at 90% completion of repolarization (MAPD90) was significantly increased and ventricular arrhythmias were observed in hearts with increased intracellular calcium concentration ([Ca(2+)]i) by using Bay K 8644, and the increase became greater in hearts treated with a combination of ATX-II and Bay K 8644 compared to Bay K 8644 alone...
April 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28428547/the-tarantula-toxin-%C3%AE-%C3%AE-trtx-pre1a-highlights-the-importance-of-the-s1-s2-voltage-sensor-region-for-sodium-channel-subtype-selectivity
#15
Joshua S Wingerd, Christine A Mozar, Christine A Ussing, Swetha S Murali, Yanni K-Y Chin, Ben Cristofori-Armstrong, Thomas Durek, John Gilchrist, Christopher W Vaughan, Frank Bosmans, David J Adams, Richard J Lewis, Paul F Alewood, Mehdi Mobli, Macdonald J Christie, Lachlan D Rash
Voltage-gated sodium (NaV) channels are essential for the transmission of pain signals in humans making them prime targets for the development of new analgesics. Spider venoms are a rich source of peptide modulators useful to study ion channel structure and function. Here we describe β/δ-TRTX-Pre1a, a 35-residue tarantula peptide that selectively interacts with neuronal NaV channels inhibiting peak current of hNaV1.1, rNaV1.2, hNaV1.6, and hNaV1.7 while concurrently inhibiting fast inactivation of hNaV1.1 and rNaV1...
April 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28425222/class-iii-antiarrhythmic-drugs-amiodarone-and-dronedarone-impair-kir-2-1-backward-trafficking
#16
Yuan Ji, Hiroki Takanari, Muge Qile, Lukas Nalos, Marien J C Houtman, Fee L Romunde, Raimond Heukers, Paul M P van Bergen En Henegouwen, Marc A Vos, Marcel A G van der Heyden
Drug-induced ion channel trafficking disturbance can cause cardiac arrhythmias. The subcellular level at which drugs interfere in trafficking pathways is largely unknown. KIR 2.1 inward rectifier channels, largely responsible for the cardiac inward rectifier current (IK1 ), are degraded in lysosomes. Amiodarone and dronedarone are class III antiarrhythmics. Chronic use of amiodarone, and to a lesser extent dronedarone, causes serious adverse effects to several organs and tissue types, including the heart. Both drugs have been described to interfere in the late-endosome/lysosome system...
April 19, 2017: Journal of Cellular and Molecular Medicine
https://www.readbyqxmd.com/read/28424991/expression-and-role-of-voltage-gated-sodium-channels-in-human-dorsal-root-ganglion-neurons-with-special-focus-on-nav1-7-species-differences-and-regulation-by-paclitaxel
#17
Wonseok Chang, Temugin Berta, Yong Ho Kim, Sanghoon Lee, Seok-Yong Lee, Ru-Rong Ji
Voltage-gated sodium channels (Navs) play an important role in human pain sensation. However, the expression and role of Nav subtypes in native human sensory neurons are unclear. To address this issue, we obtained human dorsal root ganglion (hDRG) tissues from healthy donors. PCR analysis of seven DRG-expressed Nav subtypes revealed that the hDRG has higher expression of Nav1.7 (~50% of total Nav expression) and lower expression of Nav1.8 (~12%), whereas the mouse DRG has higher expression of Nav1.8 (~45%) and lower expression of Nav1...
April 19, 2017: Neuroscience Bulletin
https://www.readbyqxmd.com/read/28423317/loss-of-nav%C3%AE-4-mediated-regulation-of-sodium-currents-in-adult-purkinje-neurons-disrupts-firing-and-impairs-motor-coordination-and-balance
#18
Joseph L Ransdell, Edward Dranoff, Brandon Lau, Wan-Lin Lo, David L Donermeyer, Paul M Allen, Jeanne M Nerbonne
The resurgent component of voltage-gated Na(+) (Nav) currents, INaR, has been suggested to provide the depolarizing drive for high-frequency firing and to be generated by voltage-dependent Nav channel block (at depolarized potentials) and unblock (at hyperpolarized potentials) by the accessory Navβ4 subunit. To test these hypotheses, we examined the effects of the targeted deletion of Scn4b (Navβ4) on INaR and on repetitive firing in cerebellar Purkinje neurons. We show here that Scn4b(-/-) animals have deficits in motor coordination and balance and that firing rates in Scn4b(-/-) Purkinje neurons are markedly attenuated...
April 18, 2017: Cell Reports
https://www.readbyqxmd.com/read/28420967/organization-and-plasticity-of-sodium-channel-expression-in-the-mouse-olfactory-and-vomeronasal-epithelia
#19
Florian Bolz, Stephanie Kasper, Bernd Bufe, Frank Zufall, Martina Pyrski
To understand the molecular basis of neuronal excitation in the mammalian olfactory system, we conducted a systematic analysis of the organization of voltage-gated sodium (Nav) channel subunits in the main olfactory epithelium (MOE) and vomeronasal organ (VNO) of adult mice. We also analyzed changes in Nav channel expression during development in these two systems and during regeneration of the MOE. Quantitative PCR shows that Nav1.7 is the predominant isoform in both adult MOE and VNO. We detected pronounced immunoreactivity for Nav1...
2017: Frontiers in Neuroanatomy
https://www.readbyqxmd.com/read/28418213/pain-thresholds-supra-threshold-pain-and-lidocaine-sensitivity-in-patients-with-erythromelalgia-including-the-i848tmutation-in-nav-1-7
#20
T Helås, D Sagafos, I P Kleggetveit, H Quiding, B Jönsson, M Segerdahl, Z Zhang, H Salter, M Schmelz, E Jørum
OBJECTIVES: Nociceptive thresholds and supra-threshold pain ratings as well as their reduction upon local injection with lidocaine were compared between healthy subjects and patients with erythromelalgia (EM). METHODS: Lidocaine (0.25, 0.50, 1.0 or 10 mg/mL) or placebo (saline) was injected intradermally in non-painful areas of the lower arm, in a randomized, double-blind manner, to test the effect on dynamic and static mechanical sensitivity, mechanical pain sensitivity, thermal thresholds and supra-threshold heat pain sensitivity...
April 18, 2017: European Journal of Pain: EJP
keyword
keyword
85898
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"