keyword
MENU ▼
Read by QxMD icon Read
search

SK channels

keyword
https://www.readbyqxmd.com/read/28065942/neuregulin-1-erbb-module-in-c-bouton-synapses-on-somatic-motor-neurons-molecular-compartmentation-and-response-to-peripheral-nerve-injury
#1
Anna Casanovas, Sara Salvany, Víctor Lahoz, Olga Tarabal, Lídia Piedrafita, Raimundo Sabater, Sara Hernández, Jordi Calderó, Josep E Esquerda
The electric activity of lower motor neurons (MNs) appears to play a role in determining cell-vulnerability in MN diseases. MN excitability is modulated by cholinergic inputs through C-type synaptic boutons, which display an endoplasmic reticulum-related subsurface cistern (SSC) adjacent to the postsynaptic membrane. Besides cholinergic molecules, a constellation of proteins involved in different signal-transduction pathways are clustered at C-type synaptic sites (M2 muscarinic receptors, Kv2.1 potassium channels, Ca(2+) activated K(+) [SK] channels, and sigma-1 receptors [S1R]), but their collective functional significance so far remains unknown...
January 9, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28050270/downregulation-of-purkinje-cell-activity-by-modulators-of-small-conductance-calcium-activated-potassium-channels-in-rat-cerebellum
#2
T V Karelina, Yu D Stepanenko, P A Abushik, D A Sibarov, S M Antonov
Small-conductance calcium-activated potassium channels (SK channels) are widely expressed in CNS tissues. Their functions, however, have not been well studied. Participation of SK channels in Purkinje cell (PC) pacemaker activity has been studied predominantly in vitro. Here we studied for the first time the effects of SK channel activation by NS309 or CyPPA on the PC simple spike frequency in vivo in adult (3 - 6 months) and aged (22 - 28 months) rats using extracellular microelectrode recordings. Both pharmacological agents caused a statistically significant decrease in the PC simple spike frequency...
October 2016: Acta Naturae
https://www.readbyqxmd.com/read/28049949/differential-contribution-of-nerve-derived-noradrenaline-to-high-k-induced-contraction-depending-on-type-of-artery
#3
Hirotake Ishida, Shin-Ya Saito, Eita Hishinuma, Tomohisa Ishikawa
High K(+)-induced contraction of arterial smooth muscle is thought to be mediated by membrane depolarization and subsequent activation of voltage-dependent Ca(2+) channels (VDCCs). In line with this, this study found that contraction induced by 80 mM K(+) was almost abolished by nifedipine (1 µM), a VDCC inhibitor, in isolated rat aorta, and was markedly suppressed in the iliac artery. However, nifedipine (1 µM) only partially suppressed high K(+)-induced contraction in the tail artery. The contractions remaining in the arteries were further reduced by non-selective cation channel (NSCC) inhibitors, including 2-aminoethoxydiphenyl borate (2-APB) (100 µM), SK&F96365 (10 µM), and 3,4-dihydro-6,7-dimethoxy-α-phenyl-N,N-bis[2-(2,3,4-trimethoxyphenyl)ethyl]-1-isoquinolineacetamide hydrochloride (LOE908) (10 µM)...
2017: Biological & Pharmaceutical Bulletin
https://www.readbyqxmd.com/read/28026020/low-pho-boosts-burst-firing-and-catecholamine-release-by-blocking-task-1-and-bk-channels-while-preserving-cav1-channels-in-mouse-chromaffin-cells
#4
Laura Guarina, David H F Vandael, Valentina Carabelli, Emilio Carbone
Mouse chromaffin cells (MCCs) generate action potential (AP) firing that regulates the Ca(2+) -dependent release of catecholamines (CAs). Recent findings indicate that MCCs possess a variety of spontaneous firing modes that span from the common "tonic-irregular" to the less frequent "burst" firing. This latter is evident in a small fraction of MCCs but occurs regularly when Nav1.3/1.7 channels are made less available or when the Slo1β2-subunit responsible for BK channel inactivation is deleted. Burst firing causes massive increases of Ca(2+) -entry and potentiates CA release ∼3...
December 27, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/28008669/r-type-ca-2-channels-couple-to-inhibitory-neurotransmission-to-the-longitudinal-muscle-in-the-guinea-pig-ileum
#5
Eileen S Rodriguez-Tapia, Vinogran Naidoo, Matthew DeVries, Alberto Perez-Medina, James J Galligan
There is evidence that R-type Ca(2+) channels contribute to synaptic transmission in the myenteric plexus. It is unknown if R-type Ca(2+) channels contribute to neuromuscular transmission. We measured the effects of the nitric oxide synthase (NOS) inhibitor, nitro L-arginine (NLA), Ca(2+) channel blockers and apamin (SK channel blocker) on neurogenic relaxations and contractions of the guinea pig ileum longitudinal muscle-myenteric plexus (LMMP) in vitro. We used intracellular recordings to measure inhibitory junction potentials (IJPs)...
December 23, 2016: Experimental Physiology
https://www.readbyqxmd.com/read/27903742/p2y6-receptor-antagonist-mrs2578-inhibits-neutrophil-activation-and-aggregated-neutrophil-extracellular-trap-formation-induced-by-gout-associated-monosodium-urate-crystals
#6
Payel Sil, Craig P Hayes, Barbara J Reaves, Patrick Breen, Shannon Quinn, Jeremy Sokolove, Balázs Rada
Human neutrophils (polymorphonuclear leukocytes [PMNs]) generate inflammatory responses within the joints of gout patients upon encountering monosodium urate (MSU) crystals. Neutrophil extracellular traps (NETs) are found abundantly in the synovial fluid of gout patients. The detailed mechanism of MSU crystal-induced NET formation remains unknown. Our goal was to shed light on possible roles of purinergic signaling and neutrophil migration in mediating NET formation induced by MSU crystals. Interaction of human neutrophils with MSU crystals was evaluated by high-throughput live imaging using confocal microscopy...
January 1, 2017: Journal of Immunology: Official Journal of the American Association of Immunologists
https://www.readbyqxmd.com/read/27874831/chronic-social-isolation-reduces-5-ht-neuronal-activity-via-upregulated-sk3-calcium-activated-potassium-channels
#7
Derya Sargin, David K Oliver, Evelyn K Lambe
The activity of serotonin (5-HT) neurons is critical for mood regulation. In a mouse model of chronic social isolation, a known risk factor for depressive illness, we show that 5-HT neurons in the dorsal raphe nucleus are less responsive to stimulation. Probing the responsible cellular mechanisms pinpoints a disturbance in the expression and function of small-conductance Ca(2+)-activated K(+) (SK) channels and reveals an important role for both SK2 and SK3 channels in normal regulation of 5-HT neuronal excitability...
November 22, 2016: ELife
https://www.readbyqxmd.com/read/27861914/a-unifying-hypothesis-for-m1-muscarinic-receptor-signalling-in-pyramidal-neurons
#8
Sameera Dasari, Corey Hill, Allan T Gulledge
KEY POINTS: Phasic release of acetylcholine (ACh) in the neocortex facilitates attentional processes. Acting at a single metabotropic receptor subtype, ACh exerts two opposing actions in cortical pyramidal neurons: transient inhibition and longer-lasting excitation. Cholinergic inhibitory responses depend on calcium release from intracellular calcium stores, and run down rapidly at resting membrane potentials when calcium stores become depleted. We demonstrate that cholinergic excitation promotes calcium entry at subthreshold membrane potentials to rapidly refill calcium stores, thereby maintaining the fidelity of inhibitory cholinergic signalling...
November 12, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27856251/local-calcium-signalling-is-mediated-by-mechanosensitive-ion-channels-in-mesenchymal-stem-cells
#9
Vladislav I Chubinskiy-Nadezhdin, Valeria Y Vasileva, Natalia A Pugovkina, Irina O Vassilieva, Elena A Morachevskaya, Nikolay N Nikolsky, Yuri A Negulyaev
Mechanical forces are implicated in key physiological processes in stem cells, including proliferation, differentiation and lineage switching. To date, there is an evident lack of understanding of how external mechanical cues are coupled with calcium signalling in stem cells. Mechanical reactions are of particular interest in adult mesenchymal stem cells because of their promising potential for use in tissue remodelling and clinical therapy. Here, single channel patch-clamp technique was employed to search for cation channels involved in mechanosensitivity in mesenchymal endometrial-derived stem cells (hMESCs)...
November 14, 2016: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/27844406/partial-bladder-outlet-obstruction-is-associated-with-decreased-expression-and-function-of-the-small-conductance-ca-2-activated-k-channel-in-guinea-pig-detrusor-smooth-muscle
#10
Ning Li, Xiaoning He, Zizheng Li, Yili Liu, Ping Wang
PURPOSE: Partial bladder outlet obstruction (PBOO) usually induces overactive bladder (OAB) associated with detrusor overactivity (DO) which is related to the increased contractility of detrusor smooth muscle (DSM). The pharmacological activation of small-conductance Ca(2+)-activated K(+) (SK) channels dramatically attenuates DSM contractility. However, the role of SK channels in the PBOO DSM is less clear. Here, we tested the hypothesis that PBOO is associated with decreased expression and function of SK channels in DSM and that the activation of SK channels is a potential target to regulate DO...
November 14, 2016: International Urology and Nephrology
https://www.readbyqxmd.com/read/27825825/changes-in-sk-channel-expression-in-the-basal-ganglia-after-partial-nigrostriatal-dopamine-lesions-in-rats-functional-consequences
#11
Christiane Mourre, Christine Manrique, Jeremy Camon, Sabrine Aidi-Knani, Thierry Deltheil, Nathalie Turle-Lorenzo, Gaelle Guiraudie-Capraz, Marianne Amalric
Parkinson's disease (PD) is a progressive neurodegenerative disease originating from the loss of dopamine (DA) neurons in the substantia nigra pars compacta (SNC). The small-conductance calcium-activated potassium (SK) channels play an essential role in the regulation of midbrain DA neuron activity patterns, as well as excitability of other types of neurons of the basal ganglia. We therefore questioned whether the SK channel expression in the basal ganglia is modified in parkinsonian rats and how this could impact behavioral performance in a reaction time task...
February 2017: Neuropharmacology
https://www.readbyqxmd.com/read/27798131/cocaine-exposure-enhances-the-activity-of-ventral-tegmental-area-dopamine-neurons-via-calcium-impermeable-nmdars
#12
Meaghan Creed, Jennifer Kaufling, Giulia R Fois, Marion Jalabert, Tifei Yuan, Christian Lüscher, Francois Georges, Camilla Bellone
: Potentiation of excitatory inputs onto dopamine neurons of the ventral tegmental area (VTA) induced by cocaine exposure allows remodeling of the mesocorticolimbic circuitry, which ultimately drives drug-adaptive behavior. This potentiation is mediated by changes in NMDAR and AMPAR subunit composition. It remains unknown how this synaptic plasticity affects the activity of dopamine neurons. Here, using rodents, we demonstrate that a single cocaine injection increases the firing rate and bursting activity of VTA dopamine neurons, and that these increases persist for 7 d...
October 19, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/27779751/distinct-subcellular-mechanisms-for-the-enhancement-of-the-surface-membrane-expression-of-sk2-channel-by-its-interacting-proteins-%C3%AE-actinin2-and-filamin-a
#13
Zheng Zhang, Hannah A Ledford, Seojin Park, Wenying Wang, Sassan Rafizadeh, Hyo Jeong Kim, Wilson Xu, Ling Lu, Victor C Lau, Anne A Knowlton, Xiao-Dong Zhang, Ebenezer N Yamoah, Nipavan Chiamvimonvat
KEY POINTS: Ion channels are transmembrane proteins that are synthesized within the cells but need to be trafficked to the cell membrane for the channels to function. Small-conductance, Ca(2+) -activated K(+) channels (SK, KCa 2) are unique subclasses of K(+) channels that are regulated by Ca(2+) inside the cells; they are expressed in human atrial myocytes and responsible for shaping atrial action potentials. We have previously shown that interacting proteins of SK2 channels are important for channel trafficking to the membrane...
October 25, 2016: Journal of Physiology
https://www.readbyqxmd.com/read/27742566/atrial-fibrillation-therapeutic-potential-of-atrial-k-channel-blockers
#14
REVIEW
Ursula Ravens, Katja E Odening
Despite the epidemiological scale of atrial fibrillation, current treatment strategies are of limited efficacy and safety. Ideally, novel drugs should specifically correct the pathophysiological mechanisms responsible for atrial fibrillation with no other cardiac or extracardiac actions. Atrial-selective drugs are directed toward cellular targets with sufficiently different characteristics in atria and ventricles to modify only atrial function. Several potassium (K(+)) channels with either predominant expression in atria or distinct electrophysiological properties in atria and ventricles can serve as atrial-selective drug targets...
October 12, 2016: Pharmacology & Therapeutics
https://www.readbyqxmd.com/read/27722784/antiarrhythmic-effect-of-the-ca-2-activated-k-sk-channel-inhibitor-ica-combined-with-either-amiodarone-or-dofetilide-in-an-isolated-heart-model-of-atrial-fibrillation
#15
Jeppe Egedal Kirchhoff, Jonas Goldin Diness, Lea Abildgaard, Majid Sheykhzade, Morten Grunnet, Thomas Jespersen
Dose is an important parameter in terms of both efficacy and adverse effects in pharmacological treatment of atrial fibrillation (AF). Both of the class III antiarrhythmics dofetilide and amiodarone have documented anti-AF effects. While dofetilide has dose-related ventricular side effects, amiodarone primarily has adverse non-cardiac effects. Pharmacological inhibition of small conductance Ca(2+)-activated K(+) (SK) channels has recently been reported to be antiarrhythmic in a number of animal AF models. In a Langendorff model of acutely induced AF on guinea pig hearts, it was investigated whether a combination of the SK channel blocker N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICA) together with either dofetilide or amiodarone provided a synergistic effect...
November 2016: Pflügers Archiv: European Journal of Physiology
https://www.readbyqxmd.com/read/27698359/observation-of-a-hybrid-state-of-tamm-plasmons-and-microcavity-exciton-polaritons
#16
Sk Shaid-Ur Rahman, Thorsten Klein, Sebastian Klembt, Jürgen Gutowski, Detlef Hommel, Kathrin Sebald
We present evidence for the existence of a hybrid state of Tamm plasmons and microcavity exciton polaritons in a II-VI material based microcavity sample covered with an Ag metal layer. The bare cavity mode shows a characteristic anticrossing with the Tamm-plasmon mode, when microreflectivity measurements are performed for different detunings between the Tamm plasmon and the cavity mode. When the Tamm-plasmon mode is in resonance with the cavity polariton four hybrid eigenstates are observed due to the coupling of the cavity-photon mode, the Tamm-plasmon mode, and the heavy- and light-hole excitons...
October 4, 2016: Scientific Reports
https://www.readbyqxmd.com/read/27683906/hypocretin-orexin-peptides-alter-spike-encoding-by-serotonergic-dorsal-raphe-neurons-through-two-distinct-mechanisms-that-increase-the-late-afterhyperpolarization
#17
Masaru Ishibashi, Iryna Gumenchuk, Kenichi Miyazaki, Takafumi Inoue, William N Ross, Christopher S Leonard
UNLABELLED: Orexins (hypocretins) are neuropeptides that regulate multiple homeostatic processes, including reward and arousal, in part by exciting serotonergic dorsal raphe neurons, the major source of forebrain serotonin. Here, using mouse brain slices, we found that, instead of simply depolarizing these neurons, orexin-A altered the spike encoding process by increasing the postspike afterhyperpolarization (AHP) via two distinct mechanisms. This orexin-enhanced AHP (oeAHP) was mediated by both OX1 and OX2 receptors, required Ca(2+) influx, reversed near EK, and decayed with two components, the faster of which resulted from enhanced SK channel activation, whereas the slower component decayed like a slow AHP (sAHP), but was not blocked by UCL2077, an antagonist of sAHPs in some neurons...
September 28, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
https://www.readbyqxmd.com/read/27646472/activation-of-atp-sensitive-potassium-channels-enhances-dmt1-mediated-iron-uptake-in-sk-n-sh-cells-in-vitro
#18
Xixun Du, Huamin Xu, Limin Shi, Zhifeng Jiang, Ning Song, Hong Jiang, Junxia Xie
Iron importer divalent metal transporter 1 (DMT1) plays a crucial role in the nigal iron accumulation in Parkinson's disease (PD). Membrane hyperpolarization is one of the factors that could affect its iron transport function. Besides iron, selective activation of the ATP-sensitive potassium (KATP) channels also contributes to the vulnerability of dopaminergic neurons in PD. Interestingly, activation of KATP channels could induce membrane hyperpolarization. Therefore, it is of vital importance to study the effects of activation of KATP channels on DMT1-mediated iron uptake function...
2016: Scientific Reports
https://www.readbyqxmd.com/read/27616575/endothelium-independent-vasorelaxant-effect-of-20-s-protopanaxadiol-on-isolated-rat-thoracic-aorta
#19
Lu Gan, Zhen-Hua Wang, Hong Zhang, Xin Zhou, Hui Zhou, Chao Sun, Jing Si, Rong Zhou, Cheng-Jun Ma, Ji Li
AIM: Ginsenosides are considered to be the major pharmacologically active ginseng constituents, whereas 20(S)-protopanaxadiol [20(S)-PPD] is the active metabolite of ginsenosides in gut. In this study we investigated the effect of 20(S)-PPD on isolated rat thoracic aortas as well as its vasorelaxant mechanisms. METHODS: Aortic rings with or without endothelium were prepared from Wistar rats and suspended in organ-chambers. The changes in tension of the preparations were recorded through isometric transducers connected to a data acquisition system...
December 2016: Acta Pharmacologica Sinica
https://www.readbyqxmd.com/read/27555660/dynamic-dna-methylation-regulates-neuronal-intrinsic-membrane-excitability
#20
Jarrod P Meadows, Mikael C Guzman-Karlsson, Scott Phillips, Jordan A Brown, Sarah K Strange, J David Sweatt, John J Hablitz
Epigenetic modifications, such as DNA cytosine methylation, contribute to the mechanisms underlying learning and memory by coordinating adaptive gene expression and neuronal plasticity. Transcription-dependent plasticity regulated by DNA methylation includes synaptic plasticity and homeostatic synaptic scaling. Memory-related plasticity also includes alterations in intrinsic membrane excitability mediated by changes in the abundance or activity of ion channels in the plasma membrane, which sets the threshold for action potential generation...
August 23, 2016: Science Signaling
keyword
keyword
38978
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"