keyword
MENU ▼
Read by QxMD icon Read
search

hcn channel

keyword
https://www.readbyqxmd.com/read/28074902/a-reduced-mechanical-model-for-camp-modulated-gating-in-hcn-channels
#1
Stephanie Weißgraeber, Andrea Saponaro, Gerhard Thiel, Kay Hamacher
We developed an in silico mechanical model to analyze the process of cAMP-induced conformational modulations in hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, which conduct cations across the membrane of mammalian heart and brain cells. The structural analysis reveals a quaternary twist in the cytosolic parts of the four subunits in the channel tetramer. This motion augments the intrinsic dynamics of the very same protein structure. The pronounced differences between the cAMP bound and unbound form include a mutual interaction between the C-linker of the cyclic nucleotide binding domain (CNBD) and the linker between the S4 and S5 transmembrane domain of the channel...
January 11, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28071723/hcn1-channels-reduce-the-rate-of-exocytosis-from-a-subset-of-cortical-synaptic-terminals
#2
Zhuo Huang, Gengyu Li, Carolina Aguado, Rafael Lujan, Mala M Shah
The hyperpolarization-activated cyclic nucleotide-gated (HCN1) channels are predominantly located in pyramidal cell dendrites within the cortex. Recent evidence suggests these channels also exist pre-synaptically in a subset of synaptic terminals within the mature entorhinal cortex (EC). Inhibition of pre-synaptic HCN channels enhances miniature excitatory post-synaptic currents (mEPSCs) onto EC layer III pyramidal neurons, suggesting that these channels decrease the release of the neurotransmitter, glutamate...
January 10, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28065805/genetic-perturbations-suggest-a-role-of-the-resting-potential-in-regulating-the-expression-of-the-ion-channels-of-the-kcna-and-hcn-families-in-octopus-cells-of-the-ventral-cochlear-nucleus
#3
Xiao-Jie Cao, Donata Oertel
Low-voltage-activated K(+) (gKL) and hyperpolarization-activated mixed cation conductances (gh) mediate currents, IKL and Ih, through channels of the Kv1 (KCNA) and HCN families respectively and give auditory neurons the temporal precision required for signaling information about the onset, fine structure, and time of arrival of sounds. Being partially activated at rest, gKL and gh contribute to the resting potential and shape responses to even small subthreshold synaptic currents. Resting gKL and gh also affect the coupling of somatic depolarization with the generation of action potentials...
January 5, 2017: Hearing Research
https://www.readbyqxmd.com/read/28054154/interstitial-cell-modulation-of-pyeloureteric-peristalsis-in-the-mouse-renal-pelvis-examined-using-fibsem-tomography-and-calcium-indicators
#4
Hikaru Hashitani, Michael J Nguyen, Haruka Noda, Retsu Mitsui, Ryuhei Higashi, Keisuke Ohta, Kei-Ichiro Nakamura, Richard J Lang
Typical and atypical smooth muscle cells (TSMCs and ASMCs, respectively) and interstitial cells (ICs) within the pacemaker region of the mouse renal pelvis were examined using focused ion beam scanning electron (FIB SEM) tomography, immunohistochemistry and Ca(2+) imaging. Individual cells within 500-900 electron micrograph stacks were volume rendered and associations with their neighbours established. 'Ribbon-shaped', Ano1 Cl(-) channel immuno-reactive ICs were present in the adventitia and the sub-urothelial space adjacent to the TSMC layer...
January 4, 2017: Pflügers Archiv: European Journal of Physiology
https://www.readbyqxmd.com/read/27965425/essential-roles-of-ampa-receptor-glua1-phosphorylation-and-presynaptic-hcn-channels-in-fast-acting-antidepressant-responses-of-ketamine
#5
Ke Zhang, Ting Xu, Zhongmin Yuan, Zhisheng Wei, Vitor Nagai Yamaki, Mingfa Huang, Richard L Huganir, Xiang Cai
Although the molecular mechanism is not clear, the clinically tested drug ketamine has rapid antidepressant action that does not require the multiple weeks of treatment needed for other antidepressant drugs to have an effect. We showed that ketamine potentiated Schaffer collateral-CA1 cell excitatory synaptic transmission in hippocampal slice preparations from rodents and enhanced the phosphorylation of the GluA1 subunit on Ser(845) of the AMPA-type glutamate receptor in the hippocampal area CA1. These effects persisted when γ-aminobutyric acid (GABA) receptors were pharmacologically blocked...
December 13, 2016: Science Signaling
https://www.readbyqxmd.com/read/27942887/predictions-of-the-contribution-of-hcn-half-maximal-activation-potential-heterogeneity-to-variability-in-intrinsic-adaptation-of-spiral-ganglion-neurons
#6
Jason Boulet, Ian C Bruce
Spiral ganglion neurons (SGNs) exhibit a wide range in their strength of intrinsic adaptation on a timescale of 10s to 100s of milliseconds in response to electrical stimulation from a cochlear implant (CI). The purpose of this study was to determine how much of that variability could be caused by the heterogeneity in half-maximal activation potentials of hyperpolarization-activated cyclic nucleotide-gated cation (HCN) channels, which are known to produce intrinsic adaptation. In this study, a computational membrane model of cat type I SGN was developed based on the Hodgkin-Huxley model plus HCN and low-threshold potassium (KLT) conductances in which the half-maximal activation potential of the HCN channel was varied and the response of the SGN to pulse train and paired-pulse stimulation was simulated...
December 9, 2016: Journal of the Association for Research in Otolaryngology: JARO
https://www.readbyqxmd.com/read/27930653/characterisation-of-development-and-electrophysiological-mechanisms-underlying-rhythmicity-of-the-avian-lymph-heart
#7
Sajjida Jaffer, Petr Valasek, Graham Luke, Munirah Batarfi, Benjamin Jason Whalley, Ketan Patel
Despite significant advances in tissue engineering such as the use of scaffolds, bioreactors and pluripotent stem cells, effective cardiac tissue engineering for therapeutic purposes has remained a largely intractable challenge. For this area to capitalise on such advances, a novel approach may be to unravel the physiological mechanisms underlying the development of tissues that exhibit rhythmic contraction yet do not originate from the cardiac lineage. Considerable attention has been focused on the physiology of the avian lymph heart, a discrete organ with skeletal muscle origins yet which displays pacemaker properties normally only found in the heart...
2016: PloS One
https://www.readbyqxmd.com/read/27911380/method-for-identifying-small-molecule-inhibitors-of-the-protein-protein-interaction-between-hcn1-and-trip8b
#8
Ye Han, Kyle A Lyman, Matt Clutter, Gary E Schiltz, Quratul-Ain Ismail, Xiangying Cheng, Chi-Hao Luan, Dane M Chetkovich
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are expressed ubiquitously throughout the brain, where they function to regulate the excitability of neurons. The subcellular distribution of these channels in pyramidal neurons of hippocampal area CA1 is regulated by tetratricopeptide repeat-containing Rab8b interacting protein (TRIP8b), an auxiliary subunit. Genetic knockout of HCN pore forming subunits or TRIP8b, both lead to an increase in antidepressant-like behavior, suggesting that limiting the function of HCN channels may be useful as a treatment for Major Depressive Disorder (MDD)...
November 11, 2016: Journal of Visualized Experiments: JoVE
https://www.readbyqxmd.com/read/27901476/the-change-of-hcn1-hcn2-mrna-expression-in-peripheral-nerve-after-chronic-constriction-injury-induced-neuropathy-followed-by-pulsed-electromagnetic-field-therapy
#9
Hui Liu, Jun Zhou, Lianbing Gu, Yunxia Zuo
Neuropathic pain is usually defined as a chronic pain state caused by peripheral or central nerve injury as a result of acute damage or systemic diseases. It remains a difficult disease to treat. Recent studies showed that the frequency of action potentials in nociceptive afferents is affected by the activity of hyperpolarization-activated cyclic nucleotide-gated cation channels (HCN) family. In the current study, we used a neuropathy rat model induced by chronic constriction injury (CCI) of sciatic nerve to evaluate the change of expression of HCN1/HCN2 mRNA in peripheral nerve and spinal cord...
November 25, 2016: Oncotarget
https://www.readbyqxmd.com/read/27813693/loss-of-hcn-channel-mediated-ih-current-following-seizures-accounts-for-movement-dysfunction
#10
Jeffery A Boychuk, G Campbell Teskey
No abstract text is available yet for this article.
November 4, 2016: Channels
https://www.readbyqxmd.com/read/27807172/nitric-oxide-modulates-hcn-channels-in-magnocellular-neurons-of-the-supraoptic-nucleus-of-rats-by-an-s-nitrosylation-dependent-mechanism
#11
Melina Pires da Silva, Davi José de Almeida Moraes, André de Souza Mecawi, José Antunes Rodrigues, Wamberto Antonio Varanda
: The control of the excitability in magnocellular neurosecretory cells (MNCs) of the supraoptic nucleus has been attributed mainly to synaptic inputs from circunventricular organs. However, nitric oxide (NO), a gaseous messenger produced in this nucleus during isotonic and short-term hypertonic conditions, is an example of a modulator that can act directly on MNCs to modulate their firing rate. NO inhibits the electrical excitability of MNCs, leading to a decrease in the release of vasopressin and oxytocin...
November 2, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/27743933/contribution-of-large-sized-primary-sensory-neuronal-sensitization-to-mechanical-allodynia-by-upregulation-of-hyperpolarization-activated-cyclic-nucleotide-gated-channels-via-cyclooxygenase-1-cascade
#12
Wei Sun, Fei Yang, Yan Wang, Han Fu, Yan Yang, Chun-Li Li, Xiao-Liang Wang, Qing Lin, Jun Chen
Under physiological state, small- and medium-sized dorsal root ganglia (DRG) neurons are believed to mediate nociceptive behavioral responses to painful stimuli. However, recently it has been found that a number of large-sized neurons are also involved in nociceptive transmission under neuropathic conditions. Nonetheless, the underlying mechanisms that large-sized DRG neurons mediate nociception are poorly understood. In the present study, the role of large-sized neurons in bee venom (BV)-induced mechanical allodynia and the underlying mechanisms were investigated...
February 2017: Neuropharmacology
https://www.readbyqxmd.com/read/27690448/structural-basis-of-tonic-inhibition-by-dimers-of-dimers-in-hyperpolarization-activated-cyclic-nucleotide-modulated-hcn-ion-channels
#13
Bryan VanSchouwen, Giuseppe Melacini
The hyperpolarization-activated cyclic-nucleotide-modulated (HCN) ion channels control rhythmicity in neurons and cardiomyocytes. Cyclic AMP (cAMP) modulates HCN activity through cAMP-dependent formation of a tetrameric gating ring spanning the intracellular region (IR) of HCN. In the absence of cAMP, the IR cAMP-binding domain (CBD) mainly samples its inactive conformation, resulting in steric clashes that destabilize the IR tetramer. Although these clashes with the inactive CBD are released through tetramer dissociation into monomers, functional mutagenesis suggests that the apo IR is not fully monomeric...
October 3, 2016: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/27668045/corlanor-ivabradine-first-hcn-channel-blocker-fda-approved-for-the-treatment-of-patients-with-heart-failure
#14
Loretta Fala
No abstract text is available yet for this article.
March 2016: American Health & Drug Benefits
https://www.readbyqxmd.com/read/27650422/central-neural-alterations-predominate-in-an-insect-model-of-nociceptive-sensitization
#15
Dennis R Tabuena, Allan Solis, Ken Geraldi, Christopher A Moffatt, Megumi Fuse
Many organisms respond to noxious stimuli with defensive maneuvers. This is noted in the hornworm, Manduca sexta, as a defensive strike response. After tissue damage, organisms typically display sensitized responses to both noxious or normally innocuous stimuli. To further understand this phenomenon, we used novel in situ and in vitro preparations based on paired extracellular nerve recordings and videography to identify central and peripheral nerves responsible for nociception and sensitization of the defensive behavior in M...
September 21, 2016: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/27633787/accumulation-of-k-in-the-synaptic-cleft-modulates-activity-by-influencing-both-vestibular-hair-cell-and-calyx-afferent-in-the-turtle
#16
Donatella Contini, Steven D Price, Jonathan J Art
KEY POINTS: In the synaptic cleft between type I hair cells and calyceal afferents, K(+) ions accumulate as a function of activity, dynamically altering the driving force and permeation through ion channels facing the synaptic cleft. High-fidelity synaptic transmission is possible due to large conductances that minimize hair cell and afferent time constants in the presence of significant membrane capacitance. Elevated potassium maintains hair cells near a potential where transduction currents are sufficient to depolarize them to voltages necessary for calcium influx and synaptic vesicle fusion...
September 16, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27621481/hcn2-ion-channels-basic-science-opens-up-possibilities-for-therapeutic-intervention-in-neuropathic-pain
#17
REVIEW
Christoforos Tsantoulas, Elizabeth R Mooney, Peter A McNaughton
Nociception - the ability to detect painful stimuli - is an invaluable sense that warns against present or imminent damage. In patients with chronic pain, however, this warning signal persists in the absence of any genuine threat and affects all aspects of everyday life. Neuropathic pain, a form of chronic pain caused by damage to sensory nerves themselves, is dishearteningly refractory to drugs that may work in other types of pain and is a major unmet medical need begging for novel analgesics. Hyperpolarisation-activated cyclic nucleotide (HCN)-modulated ion channels are best known for their fundamental pacemaker role in the heart; here, we review data demonstrating that the HCN2 isoform acts in an analogous way as a 'pacemaker for pain', in that its activity in nociceptive neurons is critical for the maintenance of electrical activity and for the sensation of chronic pain in pathological pain states...
September 15, 2016: Biochemical Journal
https://www.readbyqxmd.com/read/27585751/activation-of-5-ht2a-2c-receptors-reduces-the-excitability-of-cultured-cortical-neurons
#18
Lingli Hu, Chunhua Liu, Minyan Dang, Bin Luo, Yiping Guo, Haitao Wang
The abundant forebrain serotonergic projections are believed to modulate the activities of cortical neurons. 5-HT2 receptor among multiple subtypes of serotonin receptors contributes to the modulation of excitability, synaptic transmissions and plasticity. In the present study, whole-cell patch-clamp recording was adopted to examine whether activation of 5-HT2A/2C receptors would have any impact on the excitability of cultured cortical neurons. We found that 2,5-Dimethoxy-4-iodoamphetamine (DOI), a selective 5-HT2A/2C receptor agonist, rapidly and reversibly depressed spontaneous action potentials mimicking the effect of serotonin...
October 6, 2016: Neuroscience Letters
https://www.readbyqxmd.com/read/27583680/a-novel-intrinsic-analgesic-mechanism-the-enhancement-of-the-conduction-failure-along-polymodal-nociceptive-c-fibers
#19
Xiuchao Wang, Shan Wang, Wenting Wang, Jianhong Duan, Ming Zhang, Xiaohua Lv, Chunxiao Niu, Chao Tan, Yuanbin Wu, Jing Yang, Sanjue Hu, Junling Xing
Although conduction failure has been observed in nociceptive C-fibers, little is known regarding its significance or therapeutic potential. In a previous study, we demonstrated that C-fiber conduction failure, which is regarded as an intrinsic self-inhibition mechanism, was reduced in circumstances of painful diabetic neuropathy. In this study, we extend this finding in the complete Freund's adjuvant model of inflammatory pain and validate that the degree of conduction failure decreased and led to a greater amount of pain signals conveyed to the central nervous system...
October 2016: Pain
https://www.readbyqxmd.com/read/27569278/expression-and-cellular-localization-of-hcn-channels-in-rat-cerebellar-granule-neurons
#20
Rafael Zúñiga, Daniela González, Claudio Valenzuela, Nelson Brown, Leandro Zúñiga
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels belong to the superfamily of voltage-gated pore loop channels. In mammals, this family consists of four different subunits (HCN1-4) and their ion channels activity have been proposed to play an essential role in regulating the membrane potential of excitable cells. Here, we describe the expression and relative abundances of HCN channels in cerebellum and primary cultures of cerebellar granule neurons (CGN). Quantitative determination of mRNA expression levels demonstrated the existence of an accumulation pattern of transcripts in cerebellum that encode HCN2 > HCN3 = HCN4 > HCN1 subunits...
September 23, 2016: Biochemical and Biophysical Research Communications
keyword
keyword
31718
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"