keyword
MENU ▼
Read by QxMD icon Read
search

potassium channel

keyword
https://www.readbyqxmd.com/read/28646979/inhibition-of-rapid-delayed-rectifier-potassium-current-ikr-by-ischemia-reperfusion-and-its-recovery-by-vitamin-e-in-ventricular-myocytes
#1
Yaoxu Chen, Chunxia Yin, Yingying Yang, Zhuo Fan, Jinling Shang, Wen Tan
Ischemia/reperfusion (I/R) induces prolongation of QT interval and action potential duration (APD), which is a major cardiac electrical disorder in patients with arrhythmias. However, the mechanism of QT interval prolongation induced by I/R remains unclear. In the present study, we hypothesized that the rapid component of delayed rectifier potassium (IKr) channel plays an important role in I/R-induced QT interval prolongation. We observed a marked attenuation of IKr and a significant prolongation of action potential duration (APD) in a simulated I/R system with sodium dithionite (Na2S2O4) in ventricular myocytes of guinea pigs...
July 2017: Journal of Electrocardiology
https://www.readbyqxmd.com/read/28645860/gper-agonist-dilates-mesenteric-arteries-via-pi3k-akt-enos-and-potassium-channels-in-both-sexes
#2
Pollyana Peixoto, Rosária Dias Aires, Virgínia Soares Lemos, Nazaré Souza Bissoli, Roger Lyrio Dos Santos
AIM: The action of oestrogen has traditionally been attributed to the activation of nuclear receptors (ERα and ERβ). A third receptor, the G protein-coupled oestrogen receptor (GPER), has been described as mediator of the rapid action of oestrogen. Based on the possible protective role of oestrogen in the cardiovascular system, the present study was designed to determine whether selective GPER activation induces relaxation of mesenteric resistance arteries in both sexes and which signalling pathways are involved...
June 20, 2017: Life Sciences
https://www.readbyqxmd.com/read/28643868/the-potassium-battery-a-mobile-energy-source-for-transport-processes-in-plant-vascular-tissues
#3
REVIEW
Ingo Dreyer, Judith Lucia Gomez-Porras, Janin Riedelsberger
Contents I. II. III. IV. V. VI. VII. VIII. References SUMMARY: Plant roots absorb potassium ions from the soil and transport them in the xylem via the transpiration stream to the shoots. There, in source tissues where sufficient chemical energy (ATP) is available, K(+) is loaded into the phloem and then transported with the phloem stream to other parts of the plant; in part, transport is also back to the roots. This, at first sight, futile cycling of K(+) has been uncovered to be part of a sophisticated mechanism that (1) enables the shoot to communicate its nutrient demand to the root, (2) contributes to the K(+) nutrition of transport phloem tissues and (3) transports energy stored in the K(+) gradient between phloem cytosol and the apoplast...
June 23, 2017: New Phytologist
https://www.readbyqxmd.com/read/28643197/ampk-is-activated-early-in-cerebellar-granule-cells-undergoing-apoptosis-and-influences-vadc1-phosphorylation-status-and-activity
#4
A Bobba, E Casalino, G Amadoro, V A Petragallo, A Atlante
The neurodegeneration of cerebellar granule cells, after low potassium induced apoptosis, is known to be temporally divided into an early and a late phase. Voltage-dependent anion channel-1 (VDAC1) protein, changing from the closed inactive state to the active open state, is central to the switch between the early and late phase. It is also known that: (i) VDAC1 can undergo phosphorylation events and (ii) AMP-activated protein kinase (AMPK), the sensor of cellular stress, may have a role in neuronal homeostasis...
June 22, 2017: Apoptosis: An International Journal on Programmed Cell Death
https://www.readbyqxmd.com/read/28642134/mitochondrial-potassium-channels-in-cell-death
#5
Vanessa Checchetto, Michele Azzolini, Roberta Peruzzo, Paola Capitanio, Luigi Leanza
Mitochondria are intracellular organelles involved in several processes from bioenergetics to cell death. In the latest years, ion channels are arising as new possible targets in controlling several cellular functions. The discovery that several plasma membrane located ion channels have intracellular counterparts, has now implemented this consideration and the number of studies enforcing the understanding of their role in different metabolic pathways. In this review, we will discuss the recent updates in the field, focusing our attention on the involvement of potassium channels during mitochondrial mediated apoptotic cell death...
June 19, 2017: Biochemical and Biophysical Research Communications
https://www.readbyqxmd.com/read/28642118/current-state-of-the-art-for-cardiac-arrhythmia-gene-therapy
#6
REVIEW
J Kevin Donahue
Cardiac arrhythmias are a leading cause of morbidity and mortality. Currently available therapeutic options lack sufficient efficacy and safety. Gene therapy has been proposed for treatment of cardiac arrhythmias. This review will discuss the current state of development for arrhythmia gene therapy. So far, all published studies are short-term, proof-of-concept animal studies. Potential replacement of cardiac pacemakers has been shown for combination gene therapy using the HCN2 gene and either the gene for adenylate cyclase, the skeletal muscle isoform of the sodium channel, or a dominant negative mutant of the potassium channel responsible for resting membrane potential...
June 19, 2017: Pharmacology & Therapeutics
https://www.readbyqxmd.com/read/28641963/modulation-of-the-heart-s-electrical-properties-by-the-anticonvulsant-drug-retigabine
#7
Lena Rubi, Michael Kovar, Eva Zebedin-Brandl, Xaver Koenig, Manuel Dominguez-Rodriguez, Hannes Todt, Helmut Kubista, Stefan Boehm, Karlheinz Hilber
Retigabine, currently used as antiepileptic drug, has a wide range of potential medical uses. Administration of the drug in patients can lead to QT interval prolongation in the electrocardiogram and to cardiac arrhythmias in rare cases. This suggests that the drug may perturb the electrical properties of the heart, and the underlying mechanisms were investigated here. Effects of retigabine on currents through human cardiac ion channels, heterologously expressed in tsA-201 cells, were studied in whole-cell patch-clamp experiments...
June 19, 2017: Toxicology and Applied Pharmacology
https://www.readbyqxmd.com/read/28640632/gut-microbiota-nitric-oxide-and-microglia-as-pre-requisites-for-neurodegenerative-disorders
#8
Joyce Ka Yu Tse
Regulating fluctuating endogenous nitric oxide (NO) levels is necessary for proper physiological functions. Aberrant NO pathways are implicated in a number of neurological disorders, including Alzheimer's Disease (AD) and Parkinson's Disease. The mechanism of NO in oxidative and nitrosative stress with pathological consequences involves reactions with reactive oxygen species (e.g. superoxide) to form the highly reactive peroxynitrite, hydrogen peroxide, hypochloride ions and hydroxyl radical. NO levels are typically regulated by endogenous nitric oxide synthases (NOS), and inflammatory iNOS is implicated in the pathogenesis of neurodegenerative diseases, in which elevated NO mediates axonal degeneration and activates cyclooxygenases to provoke neuroinflammation...
June 22, 2017: ACS Chemical Neuroscience
https://www.readbyqxmd.com/read/28638923/-reconstitution-of-large-conductance-calcium-activated-potassium-channels-into-artificial-planar-lipid-bilayers
#9
Jun Cheng, Xiao-Rong Zeng, Xiao-Qiu Tan, Peng-Yun Li, Jing Wen, Liang Mao, Yan Yang
This study was aimed to establish a method to create a stable planar lipid bilayer membranes (PLBMs), in which large conductance calcium-activated potassium channels (BKCa) were reconstituted. Using spreading method, PLBMs were prepared by decane lipid fluid consisting of N2-weathered mixture of phosphatidylcholine and cholesterol at 3:1 ratio. After successful incorporation of BKCa channel into PLBMs, single channel characteristics of BKCa were studied by patch clamp method. The results showed that i) the single channel conductance of BKCa was (206...
June 25, 2017: Sheng Li Xue Bao: [Acta Physiologica Sinica]
https://www.readbyqxmd.com/read/28637770/analgesia-and-opioids-a-pharmacogenetics-shortlist-for-implementation-in-clinical-practice
#10
REVIEW
Maja Matic, Saskia N de Wildt, Dick Tibboel, Ron H N van Schaik
BACKGROUND: The use of opioids to alleviate pain is complicated by the risk of severe adverse events and the large variability in dose requirements. Pharmacogenetics (PGx) could possibly be used to tailor pain medication based on an individual's genetic background. Many potential genetic markers have been described, and the importance of genetic predisposition in opioid efficacy and toxicity has been demonstrated in knockout mouse models and human twin studies. Such predictors are especially of value for neonates and young children, in whom the assessment of efficacy or side effects is complicated by the inability of the patient to communicate this properly...
June 21, 2017: Clinical Chemistry
https://www.readbyqxmd.com/read/28637420/bioinformatics-insights-on-targets-receptors-of-amiodarone-in-human-and-acanthamoeba-castellanii
#11
Abdul Baig, Zohaib Rana, H R Ahmad
BACKGROUND: Amiodarone is prescribed for certain cardiac arrhythmias in medical practice. The drug targets and inhibits voltage dependent sodium (Na+v), calcium (Ca+2v), potassium (K+v) channels, and enzymes like cytochrome P450 and oxidosqualene cyclase. Past studies have shown that amiodarone exerts anti-amoebic effects against Trypanosoma cruzi and Acanthamoeba castellanii. OBJECTIVES: The presence of aforementioned targets and the type of cell death induced by amiodarone in these pathogenic eukaryotes like Acanthamoeba castellanii remain to be verified...
June 21, 2017: Infectious Disorders Drug Targets
https://www.readbyqxmd.com/read/28636818/critical-temperature-of-1-palmitoyl-2-oleoyl-sn-glycero-3-phosphoethanolamine-monolayers-and-its-possible-biological-relevance
#12
Jordi Hernandez Borrell, Oscar Domenech
Since transmembrane proteins (TMPs) can be obtained with sufficient purity for x-ray diffraction studies more frequently than decades ago, their mechanisms of action may now be elucidated. One of the pending issues is the actual interplay between transmembrane proteins and membrane lipids. There is strong evidence of the involvement of specific lipids with some membrane proteins, such as the potassium crystallographically sited activation channel (KcsA) of Streptomyces lividans and the secondary transporter of lactose LacY of Escherichia coli, the activities of which are associated with the presence of anionic phospholipids such as the phosphatidylglycerol (PG) and phosphatidyethanolamine (PE), respectively...
June 21, 2017: Journal of Physical Chemistry. B
https://www.readbyqxmd.com/read/28636601/crystal-structure-of-the-potassium-importing-kdpfabc-membrane-complex
#13
Ching-Shin Huang, Bjørn Panyella Pedersen, David L Stokes
Cellular potassium import systems play a fundamental role in osmoregulation, pH homeostasis and membrane potential in all domains of life. In bacteria, the kdp operon encodes a four-subunit potassium pump that maintains intracellular homeostasis, cell shape and turgor under conditions in which potassium is limiting. This membrane complex, called KdpFABC, has one channel-like subunit (KdpA) belonging to the superfamily of potassium transporters and another pump-like subunit (KdpB) belonging to the superfamily of P-type ATPases...
June 21, 2017: Nature
https://www.readbyqxmd.com/read/28633068/multi-electrode-system-for-measurement-of-transmembrane-ion-fluxes-through-living-epithelial-cells
#14
Mirosław Zając, Andrzej Lewenstam, Krzysztof Dolowy
Cystic Fibrosis (CF) is the most common fatal human genetic disease. It is caused by the defect in a single anion channel protein which affects ion and water transport across the epithelial tissue. A flat multi-electrode platform of diameter 12mm, allowing for measurement of four ions: sodium, potassium, hydrogen and chloride by exchangeable/replaceable ion-selective electrodes is described. The measurement is possible owing to the architecture of the platform which accommodates all the electrodes and inlets/outlets...
June 13, 2017: Bioelectrochemistry
https://www.readbyqxmd.com/read/28632743/in-silico-assessment-of-the-effects-of-quinidine-disopyramide-and-e-4031-on-short-qt-syndrome-variant-1-in-the-human-ventricles
#15
Cunjin Luo, Kuanquan Wang, Henggui Zhang
AIMS: Short QT syndrome (SQTS) is an inherited disorder associated with abnormally abbreviated QT intervals and an increased incidence of atrial and ventricular arrhythmias. SQT1 variant (linked to the rapid delayed rectifier potassium channel current, IKr) of SQTS, results from an inactivation-attenuated, gain-of-function mutation (N588K) in the KCNH2-encoded potassium channels. Pro-arrhythmogenic effects of SQT1 have been well characterized, but less is known about the possible pharmacological antiarrhythmic treatment of SQT1...
2017: PloS One
https://www.readbyqxmd.com/read/28630289/green-mamba-peptide-targets-type-2-vasopressin-receptor-against-polycystic-kidney-disease
#16
Justyna Ciolek, Helen Reinfrank, Loïc Quinton, Say Viengchareun, Enrico A Stura, Laura Vera, Sabrina Sigismeau, Bernard Mouillac, Hélène Orcel, Steve Peigneur, Jan Tytgat, Laura Droctové, Fabrice Beau, Jerome Nevoux, Marc Lombès, Gilles Mourier, Edwin De Pauw, Denis Servent, Christiane Mendre, Ralph Witzgall, Nicolas Gilles
Polycystic kidney diseases (PKDs) are genetic disorders that can cause renal failure and death in children and adults. Lowering cAMP in cystic tissues through the inhibition of the type-2 vasopressin receptor (V2R) constitutes a validated strategy to reduce disease progression. We identified a peptide from green mamba venom that exhibits nanomolar affinity for the V2R without any activity on 155 other G-protein-coupled receptors or on 15 ionic channels. Mambaquaretin-1 is a full antagonist of the V2R activation pathways studied: cAMP production, beta-arrestin interaction, and MAP kinase activity...
June 19, 2017: Proceedings of the National Academy of Sciences of the United States of America
https://www.readbyqxmd.com/read/28630040/endoplasmic-reticulum-associated-degradation-of-the-renal-potassium-channel-romk-leads-to-type-ii-bartter-syndrome
#17
Brighid M O'Donnell, Timothy D Mackie, Arohan R Subramanya, Jeffrey L Brodsky
Type II Bartter syndrome is caused by mutations in the Renal Outer Medullary Potassium (ROMK) channel but the molecular mechanisms underlying this disease are poorly defined. To rapidly screen for ROMK function, we developed a yeast expression system and discovered that yeast cells lacking endogenous potassium channels could be rescued by WT ROMK but not by ROMK proteins containing one of four Bartter mutations. We also found that the mutant proteins were significantly less stable than WT ROMK. However, their degradation was slowed in the presence of a proteasome inhibitor or when yeast cells contained mutations in the CDC48 or SSA1 gene, which is required for endoplasmic reticulum (ER)-associated degradation (ERAD)...
June 19, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28628030/a-novel-flexible-cuff-like-microelectrode-for-dual-purpose-acute-and-chronic-electrical-interfacing-with-the-mouse-cervical-vagus-nerve
#18
April Shawn Caravaca, Téa Tsaava, Laura Goldman, Harold Silverman, Gary Riggott, Sangeeta Chavan, Chad Bouton, Kevin J Tracey, Robert Desimone, Ed Boyden, Harbaljit Singh Sohal, Peder S Olofsson
OBJECTIVE: Neural reflexes establish homeostasis and regulate the immune system. Advances in bioelectronic medicine indicate that electrical stimulation of the vagus nerve can be used to treat inflammatory disease, yet the understanding of neural signals that regulate inflammation is incomplete. Current interfaces with the vagus nerve do not permit effective chronic stimulation or recording in mouse models, which is vital to studying the molecular and neurophysiological mechanisms that control inflammation homeostasis in health and disease...
June 19, 2017: Journal of Neural Engineering
https://www.readbyqxmd.com/read/28627809/ivabradine-reduces-digitalis-induced-ventricular-arrhythmias
#19
Gerrit Frommeyer, Jan Weller, Christian Ellermann, Nils Bögeholz, Patrick Leitz, Dirk G Dechering, Simon Kochhäuser, Kristina Wasmer, Lars Eckardt
The I(f) channel inhibitor ivabradine is recommended for treatment of heart failure but also affects potassium currents and thereby prolongs ventricular repolarization. The aim of the present study was to examine the electrophysiological effects of ivabradine on digitalis-induced ventricular arrhythmias. Thirteen rabbit hearts were isolated and Langendorff-perfused. After obtaining baseline data, the digitalis glycoside ouabain was infused (0.2μM). Monophasic action potentials and ECG showed a significant abbreviation of QT interval (-34ms,p<0...
June 19, 2017: Basic & Clinical Pharmacology & Toxicology
https://www.readbyqxmd.com/read/28626074/a-type-potassium-channels-contribute-to-prorenin-increase-of-firing-activity-in-hypothalamic-vasopressin-neurosecretory-neurons
#20
Soledad Pitra, Javier E Stern
Recent studies support an important contribution of prorenin (PR) and its receptor (PRR) to the regulation of hypothalamic sympathetic and neurosecretory outflows to the cardiovascular system, including systemic release of vasopressin (VP), both under physiological and cardiovascular disease conditions. Still, the identification of precise cellular mechanisms and neuronal/molecular targets remain unknown. We recently showed that PRR is expressed in VP neurons, and that their activation increases neuronal activity...
June 16, 2017: American Journal of Physiology. Heart and Circulatory Physiology
keyword
keyword
38976
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"