Read by QxMD icon Read

Bk channel disease

Khaled Boobés, Robert M Rosa, Daniel Batlle
Ogilvie's syndrome, or acute colonic pseudo-obstruction, is characterized by massive dilation of the colon without mechanical obstruction. Water and electrolytes often can be sequestered in the dilated intestinal loops resulting in profuse and watery diarrhea as well as hypokalemia. We report an anuric, end-stage renal disease (ESRD) patient undergoing peritoneal dialysis (PD) who developed acute colonic pseudo-obstruction causing a prolonged hospitalization. He also developed severe hypokalemia with a serum potassium (K+) as low as 2...
December 27, 2016: Clinical Nephrology
Yoshinori Nishijima, Sheng Cao, Dawid S Chabowski, Ankush Korishettar, Alyce Ge, Xiaodong Zheng, Rodney Sparapani, David D Gutterman, David X Zhang
RATIONALE: Hydrogen peroxide (H2O2) regulates vascular tone in the human microcirculation under physiological and pathophysiological conditions. It dilates arterioles by activating BKCa channels in subjects with coronary artery disease (CAD), but its mechanisms of action in subjects without CAD (non-CAD) as compared to those with CAD remain unknown. OBJECTIVE: We hypothesize that H2O2-elicited dilation involves different K(+) channels in non-CAD versus CAD, resulting in an altered capacity for vasodilation during disease...
November 21, 2016: Circulation Research
Rajeev B Tajhya, Xueyou Hu, Mark R Tanner, Redwan Huq, Natee Kongchan, Joel R Neilson, George G Rodney, Frank T Horrigan, Lubov T Timchenko, Christine Beeton
Myoblasts are mononucleated precursors of myofibers; they persist in mature skeletal muscles for growth and regeneration post injury. During myotonic dystrophy type 1 (DM1), a complex autosomal-dominant neuromuscular disease, the differentiation of skeletal myoblasts into functional myotubes is impaired, resulting in muscle wasting and weakness. The mechanisms leading to this altered differentiation are not fully understood. Here, we demonstrate that the calcium- and voltage-dependent potassium channel, KCa1...
October 20, 2016: Cell Death & Disease
Zhi-Gang Huang, Hao-Wen Liu, Zhen-Zhen Yan, Sheng Wang, Lu-Yang Wang, Jiu-Ping Ding
Large-conductance Ca(2+)- and voltage- activated potassium (MaxiK or BK) channels are composed of a pore-forming α subunit (Slo) and four types of auxiliary β subunits or just a pore-forming α subunit. Although multiple N-linked glycosylation sites in the extracellular loop of β subunits have been identified, very little is known about how glycosylation influences the structure and function of BK channels. Using a combination of site-directed mutagenesis, western blot and patch-clamp recordings, we demonstrated that three sites in the extracellular loop of β2 subunit are N-glycosylated (N-X-T/S at N88, N96 and N119)...
October 3, 2016: Channels
Xi Zoë Zhong, Xue Sun, Qi Cao, Gaofeng Dong, Raphael Schiffmann, Xian-Ping Dong
Efficient lysosomal Ca(2+) release plays an essential role in lysosomal trafficking. We have recently shown that lysosomal big conductance Ca(2+)-activated potassium (BK) channel forms a physical and functional coupling with the lysosomal Ca(2+) release channel Transient Receptor Potential Mucolipin-1 (TRPML1). BK and TRPML1 forms a positive feedback loop to facilitate lysosomal Ca(2+) release and subsequent lysosome membrane trafficking. However, it is unclear whether the positive feedback mechanism is common for other lysosomal storage diseases (LSDs) and whether BK channel agonists rescue abnormal lysosomal storage in LSDs...
September 27, 2016: Scientific Reports
Anusha Mishra
Astrocytes are the most common glial cells in the brain with fine processes and endfeet that intimately contact both neuronal synapses and the cerebral vasculature. They play an important role in mediating neurovascular coupling (NVC) via several astrocytic Ca(2+) -dependent signalling pathways such as K(+) release through BK channels, and the production and release of arachidonic acid metabolites. They are also involved in maintaining the resting tone of the cerebral vessels by releasing ATP and COX-1 derivatives...
September 13, 2016: Journal of Physiology
Jie Tao, Zhen Lan, Yunman Wang, Hongya Hei, Lulu Tian, Wanma Pan, Xuemei Zhang, Wen Peng
Large-conductance calcium-activated potassium (BK) channels are currently considered as vital players in a variety of renal physiological processes. In podocytes, BK channels become active in response to stimuli that increase local cytosolic Ca(2+), possibly secondary to activation of slit diaphragm TRPC6 channels by chemical or mechanical stimuli. Insulin increases filtration barrier permeability through mobilization of BK channels. In mesangial cells, BK channels co-expressed with β1 subunits act as a major component of the counteractive response to contraction in order to regulate glomerular filtration...
2016: Frontiers in Physiology
Aravind S Kshatri, Qin Li, Jiusheng Yan, Roddy J Large, Gerard P Sergeant, Noel G McHale, Keith D Thornbury, Mark A Hollywood
Large conductance, voltage and Ca(2+) activated K(+) channels (BK channels) are abundantly expressed throughout the body and are important regulators of smooth muscle tone and neuronal excitability. Their dysfunction is implicated in various diseases including overactive bladder, hypertension and erectile dysfunction. Therefore, BK channel openers bear significant therapeutic potential to treat the above diseases. GoSlo-SR compounds were designed to be potent and efficacious BK channel openers. Although their structural activity relationships, activation in both BKα and BKαβ channels and the hypothetical mode of action of these compounds has been studied in detail in recent years, their effectiveness to open the BKαγ channels still remains unexplored...
July 20, 2016: Channels
Hongya Hei, Jianjun Gao, Jibin Dong, Jie Tao, Lulu Tian, Wanma Pan, Hongyu Wang, Xuemei Zhang
Large conductance calcium-activated potassium (BK) channels participate in many important physiological functions in excitable tissues such as neurons, cardiac and smooth muscles, whereas the knowledge of BK channels in bone tissues and osteoblasts remains elusive. To investigate the role of BK channels in osteoblasts, we used transcription activator-like effector nuclease (TALEN) to establish a BK knockout cell line on rat ROS17/2.8 osteoblast, and detected the proliferation and mineralization of the BK-knockout cells...
July 2016: Molecules and Cells
T Hoshi, S H Heinemann
Voltage- and Ca(2+)-activated K(+) channels of big conductance (BK channels) are abundantly found in various organs and their relevance for smooth muscle tone and neuronal signaling is well documented. Dysfunction of BK channels is implicated in an array of human diseases involving many organs including the nervous, pulmonary, cardiovascular, renal, and urinary systems. In humans a single gene (KCNMA1) encodes the pore-forming α subunit (Slo1) of BK channels, but the channel properties are variable because of alternative splicing, tissue- and subcellular-specific auxiliary subunits (β, γ), posttranslational modifications, and a multitude of endogenous signaling molecules directly affecting the channel function...
2016: International Review of Neurobiology
M J Shipston, L Tian
Large conductance calcium- and voltage-activated potassium (BK) channels are ubiquitously expressed and play an important role in the regulation of an eclectic array of physiological processes. Their diverse functional role requires channels with a wide variety of properties even though the pore-forming α-subunit is encoded by a single gene, KCNMA1. To achieve this, BK channels exploit some of the most fundamental posttranscriptional and posttranslational mechanisms that allow proteomic diversity to be generated from a single gene...
2016: International Review of Neurobiology
Zoltán Pethő, Mark R Tanner, Rajeev B Tajhya, Redwan Huq, Teresina Laragione, Gyorgy Panyi, Pércio S Gulko, Christine Beeton
BACKGROUND: Fibroblast-like synoviocytes (FLS) in rheumatoid arthritis (RA-FLS) contribute to joint inflammation and damage characteristic of the disease. RA-FLS express KCa1.1 (BK, Slo1, MaxiK, KCNMA1) as their major plasma membrane potassium channel. Blocking KCa1.1 reduces the invasive phenotype of RA-FLS and attenuates disease severity in animal models of RA. This channel has therefore emerged as a promising therapeutic target in RA. However, the pore-forming α subunit of KCa1.1 is widely distributed in the body, and blocking it induces severe side effects, thus limiting its value as a therapeutic target...
2016: Arthritis Research & Therapy
A Asmar, R Barrett-Jolley, A Werner, R Kelly, M Stacey
Chondrocytes are the uniquely resident cells found in all types of cartilage and key to their function is the ability to respond to mechanical loads with changes of metabolic activity. This mechanotransduction property is, in part, mediated through the activity of a range of expressed transmembrane channels; ion channels, gap junction proteins, and porins. Appropriate expression of ion channels has been shown essential for production of extracellular matrix and differential expression of transmembrane channels is correlated to musculoskeletal diseases such as osteoarthritis and Albers-Schönberg...
April 2, 2016: Organogenesis
Adrian Kis, Stefanie Krick, Nathalie Baumlin, Matthias Salathe
Large-conductance, calcium-activated, and voltage-gated K(+) (BK) channels are expressed in many tissues of the human body, where they play important roles in signaling not only in excitable but also in nonexcitable cells. Because BK channel properties are rendered in part by their association with four β and four γ subunits, their channel function can differ drastically, depending on in which cellular system they are expressed. Recent studies verify the importance of apically expressed BK channels for airway surface liquid homeostasis and therefore of their significant role in mucociliary clearance...
April 2016: Annals of the American Thoracic Society
Jolene Atia, Conor McCloskey, Anatoly S Shmygol, David A Rand, Hugo A van den Berg, Andrew M Blanks
Uterine smooth muscle cells remain quiescent throughout most of gestation, only generating spontaneous action potentials immediately prior to, and during, labor. This study presents a method that combines transcriptomics with biophysical recordings to characterise the conductance repertoire of these cells, the 'conductance repertoire' being the total complement of ion channels and transporters expressed by an electrically active cell. Transcriptomic analysis provides a set of potential electrogenic entities, of which the conductance repertoire is a subset...
April 2016: PLoS Computational Biology
Thomas M Leurgans, Maria Bloksgaard, Jonathan R Brewer, Luis A Bagatolli, Maise H Fredgart, Kristoffer Rosenstand, Maria L Hansen, Lars M Rasmussen, Akhmadjon Irmukhamedov, Jo Gr De Mey
BACKGROUND AND PURPOSE: We tested the hypothesis that in resistance arteries from cardiovascular disease (CVD) patients, effects of an endothelium-dependent vasodilator depend on the contractile stimulus. EXPERIMENTAL APPROACH: Arteries dissected from parietal pericardium of cardiothoracic surgery patients were studied by myography and imaging techniques. Segments were sub-maximally contracted by K(+) , the TxA2 analogue U46619 or endothelin-1 (ET-1). KEY RESULTS: Relaxing effects of Na-nitroprusside were comparable, but those of bradykinin (BK) were bigger in the presence of ET-1 compared with K(+) or U46619...
May 2016: British Journal of Pharmacology
Jingyu Zou, Min Wang, Osamu Uchiumi, Yuan Shui, Yasuhito Ishigaki, Xiaoyan Liu, Nobuyoshi Tajima, Takuya Akai, Hideaki Iizuka, Nobuo Kato
Brain injury accelerates amyloid-β (Aβ) deposits and exacerbates Alzheimer's disease (AD). Accumulation of intracellular soluble Aβ impairs cognition prior to emergence of Aβ plaques. However, it is not known whether brain injury affects learning impairment attributable to intracellular soluble Aβ. We made a small injury by injecting glutamate into the parietal cortex in 3xTg AD mice of 4-5 months old, at which age soluble Aβ is accumulated without Aβ deposits. The size of glutamate-induced lesion was significantly larger than that of saline-injected control lesion...
April 15, 2016: Brain Research
Aida Oliván-Viguera, Marta Sofía Valero, Estéfano Pinilla, Sara Amor, Ángel Luis García-Villalón, Nichole Coleman, Celia Laría, Víctor Calvín-Tienza, Ángel-Luis García-Otín, José M Fernández-Fernández, M Divina Murillo, José A Gálvez, María D Díaz-de-Villegas, Ramón Badorrey, Ulf Simonsen, Luis Rivera, Heike Wulff, Ralf Köhler
Opening of intermediate-conductance calcium-activated potassium channels (KC a 3.1) produces membrane hyperpolarization in the vascular endothelium. Here, we studied the ability of two new KC a 3.1-selective positive-gating modulators, SKA-111 and SKA-121, to (1) evoke porcine endothelial cell KC a 3.1 membrane hyperpolarization, (2) induce endothelium-dependent and, particularly, endothelium-derived hyperpolarization (EDH)-type relaxation in porcine coronary arteries (PCA) and (3) influence coronary artery tone in isolated rat hearts...
August 2016: Basic & Clinical Pharmacology & Toxicology
Mu Yu, San-ling Liu, Pei-bei Sun, Hao Pan, Chang-lin Tian, Long-hua Zhang
Large conductance, Ca(2+)-activated potassium (BK) channels play important roles in the regulation of neuronal excitability and the control of smooth muscle contractions. BK channels can be activated by changes in both the membrane potential and intracellular Ca(2+) concentrations. Here, we provide an overview of the structural and pharmacological properties of BK channel blockers. First, the properties of different venom peptide toxins from scorpions and snakes are described, with a focus on their characteristic structural motifs, including their disulfide bond formation pattern, the binding interface between the toxin and BK channel, and the functional consequence of the blockage of BK channels by these toxins...
January 2016: Acta Pharmacologica Sinica
L N Maslov, N V Naryzhnaya, J-M Pei, Y Zhang, H Wang, I J Khaliulin, Yu B Lishmanov
It is well known that cardiovascular disease and in particular acute myocardial infarction are a major cause of death among working-age population in Russia. Some of the patients die after successful recanalization of the infarct-related coronary artery as a result of ischemic and reperfusion injury of the heart. It is obvious that there is an urgent need to develop new approaches to prevention reoxygenation heart damages. In this regard the study of adaptive phenomenon postconditioning is of particular interest...
June 2015: Rossiĭskii Fiziologicheskiĭ Zhurnal Imeni I.M. Sechenova
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"