• The protein encoded by this gene is part of a potentially heterotetrameric voltage-independent potassium channel that is activated by intracellular calcium. (thermofisher.com)
  • Potassium channels whose activation is dependent on intracellular calcium concentrations. (harvard.edu)
  • It was soon shown that this effect depended on an increase in intracellular calcium (Cai2+) ( Whittam, 1968 ), and that the calcium sensor was located at the inside of the membrane ( Blum and Hoffman, 1972 ). (conicyt.cl)
  • Although airway smooth muscle (ASM) contraction is initiated by calcium release from intracellular stores, there is considerable evidence that the control of membrane potential by potassium channels is an important factor in regulating ASM constriction. (americanasthmafoundation.org)
  • Changes in intracellular calcium not only modify glial physiology, but they also seem to be involved in complex intercellular communication networks (for review, see Finkbeiner, 1993 ). (jneurosci.org)
  • Neuromodulatory transmitters engage G-protein coupled receptors (GPCRs), activating intracellular signaling cascades that then can directly activate or modify the properties of ion channels. (frontiersin.org)
  • Note that inhibition of K V 7 channels is a downstream consequence of Ca V 3.2 modulation due to changes in intracellular calcium concentration. (frontiersin.org)
  • The process restores the excess of intracellular potassium and extracellular sodium and reinstates the negative resting membrane potential. (medscape.com)
  • Here, his work (sponsored by two American Heart Association Founder's Affiliate Postdoctoral Fellowships) focused on the role of vascular ion channels and G-protein coupled receptors in the control of brain blood flow. (umaryland.edu)
  • Intermediate duration LTP (LTP 2) was associated with Ca increase in dendritic branches, due to activation of NMDA receptors and local IP3 receptors (IP3Rs). (yale.edu)
  • G-protein-coupled receptors and ion channels present on the endothelial cells and vascular smooth muscle cells (SMCs) that form the walls of cerebral blood vessels initiate many of the signaling cascades that enable these intrinsic adaptive processes. (elifesciences.org)
  • The kainate-induced increase was highly sensitive to Gd 3+ or Na + removal in most neurons but insensitive in a minority subpopulation ("cobalt-positive cells"), suggesting that a fourth route of neuronal Zn 2+ entry is through the Ca 2+ -permeable channels gated by certain subtypes of AMPA or kainate receptors. (jneurosci.org)
  • This gene is similar to other KCNN family potassium channel genes, but it differs enough to possibly be considered as part of a new subfamily. (thermofisher.com)
  • Her laboratory is particularly interested in the voltage-gated Kv1.3 and the calcium-activated KCa3.1 channels in immune cells and in the calcium-activated KCa2/3 channels in the cardiovascular and nervous system. (ucdavis.edu)
  • Previously, we had shown that the BK channel accessory beta1 subunit is required for BK channel function in vascular smooth muscle and bladder smooth muscle. (americanasthmafoundation.org)
  • Knockout of the beta1 subunit results in BK channels that fail to open, increased calcium influx and increased tone. (americanasthmafoundation.org)
  • It is the small subunit of the MHC class I molecule. (lookformedical.com)
  • Finally, it seems appropriate to consider the "sodium channel syndrome" (mutations in the gene of the α subunit of the sodium channel, SCN5A gene) as a single clinical entity that may manifest in a wide range of phenotypes, to thus have a better insight on these cardiac syndromes and potential outcomes for their clinical treatment. (bvsalud.org)
  • elevation, while cation channel blockers, free radical scavengers, low extracellular [Ca2+], transition metal chelators, and removal of the cell wall inhibit this reaction. (deepdyve.com)
  • Later experiments, in which six different calmodulin-inhibitory drugs were tested on the Ca-activated K conductance of human RBCs, showed that all were potent inhibitors of this conductance and that their effect showed a correlation coefficient of 0.98 with that found on RBC Ca-ATPase, a membrane enzyme known to be activated by calmodulin ( Lackington and Orrego, 1981 ). (conicyt.cl)
  • Apamin-sensitive calcium-activated potassium currents in rabbit ventricles with chronic myocardial infarction. (harvard.edu)
  • Cerebellar ataxia by enhanced Ca(V)2.1 currents is alleviated by Ca2+-dependent K+-channel activators in Cacna1a(S218L) mutant mice. (harvard.edu)
  • These conclusions were, however, apparently contradicted by elegant experiments done on internally-perfused snail neurons, in which neither the injection of calmodulin, nor of the calmodulin-antagonist, trifluoperazine, were able to modify Ca-activated K currents ( Levitan and Levitan, 1986 ). (conicyt.cl)
  • Exogenous ascorbate also induces a moderate increase in programmed cell death symptoms in intact roots, but it does not activate Ca2+ influx currents in patch-clamped root protoplasts. (deepdyve.com)
  • The recently identified 2-pore domain potassium (K2P) channels are believed to be responsible for leak K + currents. (medscape.com)
  • Short-term treatment (3 hours) with 1 μ M metformin reversed the decrease of IK Ca and SK Ca currents induced by AGE incubation for 3 hours without changing the channel expression or the AMPK activation in HUVECs. (aspetjournals.org)
  • The main mechanism underlying AHP is the activation of voltage- and calcium-dependent potassium currents. (eneuro.org)
  • The inhibitory action of the AHP is generally attributed to the potassium channels that prevent excitatory currents to bring the membrane potential ( V m ) to the AP threshold ( Rubin and Cleland, 2006 ). (eneuro.org)
  • The expression level of KCa2.3 channels in the endothelium influences arterial tone by setting arterial smooth muscle membrane potential. (wikipedia.org)
  • The sustained activity of KCa2.3 channels induces a sustained hyperpolarisation of the endothelial cell membrane potential, which is then carried to nearby smooth muscle through gap junctions. (wikipedia.org)
  • Increases in the diameter of small resistance arteries and arterioles occur secondary to processes that can be dependent or independent of changes in membrane potential. (ox.ac.uk)
  • The concentration gradients are maintained by the sodium/potassium ATP pump (in an energy-dependent process) that transports sodium ions out of the cell and potassium ions into the cell. (medscape.com)
  • This active transport creates a concentration gradient that favors the extracellular diffusion of potassium ions. (medscape.com)
  • In addition, because the nerve membrane is permeable to potassium ions and impermeable to sodium ions, 95% of the ionic leak in excitable cells is caused by K + ions in the form of an outward flux, accounting for the negative resting potential. (medscape.com)
  • Once membrane depolarization is complete, the membrane becomes impermeable to sodium ions again, and the conductance of potassium ions into the cell increases. (medscape.com)
  • When it is active, TRPA1 forms a channel that allows signals known as calcium ions to enter the cell, which ultimately leads to arteries in the brain becoming wider. (elifesciences.org)
  • The essential metal ions for humans are the bulk metals sodium, potassium, calcium and magnesium and the trace metals manganese, iron, cobalt, copper, zinc and molybdenum, and, after outlining why they are required, we summarise the circumstances in which certain of them can be toxic. (rsc.org)
  • The objective of this study was to investigate the contribution of small or intermediate conductance calcium-activated potassium channels (SKca & IKca) in modulating vascular function of MA in this model. (pacific.edu)
  • Dr. Wulff is considered an expert on potassium channel pharmacology and the work in her laboratory focuses on the design of new potassium channel modulators as research tools and as potential drugs. (ucdavis.edu)
  • K+ channel modulators for the treatment of neurological disorders and autoimmune diseases. (ucdavis.edu)
  • Effects of calcium-activated potassium channel modulators on afterhyperpolarizing potentials in identified motor and mechanosensory neurons of the medicinal leech. (harvard.edu)
  • In hypothalamic neurons, modulators such as neuropeptide Y (NPY) and adenosine depress glutamatergic transmission by either a pertussis toxin (PTx)-sensitive G-protein-coupled pathway or by inhibition of voltage-activated calcium channels (VACCs). (jneurosci.org)
  • On the other hand, these recent studies apparently also support the lack of involvement of calmodulin in the gating of the BK channels studied in Helix neurons by Levitan and Levitan (1986) . (conicyt.cl)
  • Endothelium-dependent hyperpolarizing factors (EDHF) is an important regulator of vascular tone, especially in small vessels such as MA. (pacific.edu)
  • Longden T , Nelson M (2015) " Vascular Inward Rectifier K+ Channels as External K+ Sensors in the Control of Cerebral Blood Flow " Microcirculation , 22(3): 183-196. (umaryland.edu)
  • The NMDA-induced increase was only partly sensitive to Gd 3+ or to removal of extracellular Na + , consistent with a third route of entry directly through NMDA receptor-gated channels. (jneurosci.org)
  • influx via the Gardos channel (IK(Ca)) in human erythrocytes. (lu.se)
  • Activation is followed by membrane hyperpolarization, which promotes calcium influx. (thermofisher.com)
  • This neurotoxicity appears also to be mediated by Zn 2+ influx, in large part through voltage-gated Ca 2+ channels and also through NMDA receptor-gated channels ( Koh and Choi, 1994 ) and Ca 2+ -permeable AMPA/kainate receptor-gated channels ( Yin and Weiss, 1995 ). (jneurosci.org)
  • SK3 (small conductance calcium-activated potassium channel 3) also known as KCa2.3 is a protein that in humans is encoded by the KCNN3 gene. (wikipedia.org)
  • Estrogen not only enhances transcription of the KCNN3 gene, but also affects the activity of KCa2.3 channels on the cell membrane. (wikipedia.org)
  • Isolation of a novel potassium channel gene hSKCa3 containing a polymorphic CAG repeat: a candidate for schizophrenia and bipolar disorder? (wikipedia.org)
  • Our results are not consistent with the idea that EDHF is K + activating Na + /K + ATPase and K(IR) in this blood vessel. (lu.se)
  • Malate is synthesized in guard cells via starch degradation that is induced by the activated H + -ATPase 27 . (nature.com)
  • however, the signaling components connecting the phototropins, the H + -ATPase, and the anion channels remain unknown. (nature.com)
  • Hyperpolarization reduces the opening of voltage-gated calcium channels and thereby the stimulus for contraction of these resistance vessels. (ox.ac.uk)
  • The stimulus for smooth muscle cell (SMC) hyperpolarization can occur directly via opening K(+)-channels expressed within those cells, but can also occur in response to stimulation of endothelial cells (ECs). (ox.ac.uk)
  • This endothelium-dependent hyperpolarization (EDH) of smooth muscle often occurs in response to agonists that stimulate a rise in the Ca(2+) concentration of ECs, which in turn can open Ca(2+)-activated K-channels to hyperpolarize the ECs, and if present, patent gap junctions connecting ECs to SMCs (myoendothelial gap junctions) can potentially enable direct electrical coupling. (ox.ac.uk)
  • Based on differences in unitary conductances, sensitivity to drugs, and voltage-dependence, this allowed the classification of the channels as small (SK), with unitary conductances of 4 - 14 pS that are blocked by apamin and are insensitive to voltage. (conicyt.cl)
  • On the other hand, BK channels have an aspartate-rich Ca-sensing region (a «calcium bowl») in the channel protein itself, which confers most of the Ca-sensitivity to the channel, although a second Ca-sensor also seems to be present ( Schreiber and Salkoff, 1997 ). (conicyt.cl)
  • Intriguingly, the replacement of gluconate with ascorbate in the patch-clamp pipette reveals a large ascorbate efflux current, which shows sensitivity to the anion channel blocker, anthracene-9-carboxylic acid (A9C), indicative of the ascorbate release via anion channels. (deepdyve.com)
  • The inhibition could be mimicked by the L-type calcium channel blocker nimodipine (1 μ m ) as well as by protein kinase C (PKC) activators phorbol 12,13-dibutyrate (10 μ m ) and phorbol 12-myristate 13-acetate (500 n m ), and blocked by the PKC inactivator (±)-1-(5-isoquinolinesulfonyl)-2-methylpiperazine (200 μ m ), suggesting a mechanism involving PKC modulation of L-type calcium channels. (jneurosci.org)
  • CBC1/CBC2 redundantly stimulate stomatal opening by inhibition of S-type anion channels in response to both BL and low concentrations of CO 2 . (nature.com)
  • Case Report on: Very Early Afterdepolarizations in HiPSC-Cardiomyocytes-An Artifact by Big Conductance Calcium Activated Potassium Current (Ibk,Ca). Cells. (harvard.edu)
  • The presence in human red blood cells (RBCs) of a K permeability that was greatly enhanced by calcium was first reported by Gardós (1958) . (conicyt.cl)
  • Intermediate (IK) channels, on the other hand, have conductances of 11- 40 pS, are voltage-independent, may be blocked by iberiotoxin and charybdotoxin (Ch Tx), and are found in red and white blood cells, colon, lung, pancreas, and other tissues. (conicyt.cl)
  • The type III mGluR agonist l -2-amino-4-phosphonobutyrate consistently inhibited 5HT-evoked calcium rises, whereas in a smaller number of cells quisqualate and L-CCG-I showed both inhibitory and additive effects. (jneurosci.org)
  • Hypoxia and ischemia are linked to oxidative stress, which can activate the oxidant-sensitive transient receptor potential ankyrin 1 (TRPA1) channel in cerebral artery endothelial cells, leading to vasodilation. (elifesciences.org)
  • We hypothesized that TRPA1 channels in endothelial cells are activated by hypoxia-derived reactive oxygen species, leading to cerebral artery dilation and reduced ischemic damage. (elifesciences.org)
  • Loss of TRPA1 channels in endothelial cells increased cerebral infarcts, whereas TRPA1 activation with cinnamaldehyde reduced infarct in wildtype, but not Trpa1 ecKO, mice. (elifesciences.org)
  • The zygote then divides into a series of smaller cells, called blastomeres. (canadaassignmenthelp.com)
  • Longden T , Dabertrand F, Hill-Eubanks D, Hammack S, Nelson M (2014) " Stress-Induced Glucocorticoid Signaling Remodels Neurovascular Coupling Through Impairment of Cerebrovascular Inwardly Rectifying K+ Channel Function " Proceedings of the National Academy of Sciences USA , 111(20): 7462-7. (umaryland.edu)
  • The present study was designed to investigate the effect of metformin on the impairment of intermediate-conductance and small-conductance Ca 2+ -activated potassium channels (IK Ca and SK Ca )-mediated relaxation in diabetes and the underlying mechanism. (aspetjournals.org)
  • Small (SK) and intermediate (IK) conductance calcium-activated potassium channels are candidate ion channels for the regulation of excitability in nociceptive neurones. (dundee.ac.uk)
  • Calcium plays a key role as a second messenger system in astrocytes, both in regulation of many subcellular processes and in long distance intercellular signaling. (jneurosci.org)
  • Neuromodulatory regulation of ion channels affects how ion channels respond to voltage deflections on short and long time scales, thus affecting how certain features of synaptic input are transformed into neuronal output. (frontiersin.org)
  • Functional states of the sodium channel (closed, open, and inactivated) and their structure help to understand the cardiac regulation processes. (bvsalud.org)
  • Axonal ion channels are important for many aspects of neuronal function, from the initiation and propagation of APs to the release of neurotransmitter ( Figure 1A ). (frontiersin.org)
  • Hariharan A, Weir N, Robertson C, He L, Betsholtz C, Longden T (2020) " The ion channel and GPCR signaling toolkit of CNS pericytes " Frontiers in Cellular Neuroscience 14: 423. (umaryland.edu)
  • Peripheral activation of nociceptors is modulated by a number of chemical substances, which are produced and released when there is cellular damage (e.g. potassium, serotonin, bradykinin, histamine, prostogladins, leukotrienes and substance P). (postgraduateorthopaedics.co.uk)
  • In contrast, mGluRs modulated serotonin (5HT)-evoked calcium rises through a different mechanism. (jneurosci.org)
  • Of these, four: sodium, potassium, calcium and magnesium, can be considered as 'bulk elements', and together constitute approximately 99% of the metal ion content of the human body. (rsc.org)
  • Patch recordings yield an approximate channel density of 7 pS/micron^2 in juvenile rats (yale.edu)
  • Heart relaxation also stands out as an active process, dependent on the energetic output and on specific ion and enzymatic actions, with the role of sodium channel being outstanding in the functional process. (bvsalud.org)
  • EPR spectroscopy measurements demonstrate that salinity (NaCl) triggers the accumulation of root apoplastic ascorbyl radicals in an A9C-dependent manner, confirming that l-ascorbate leaks through anion channels under depolarization. (deepdyve.com)
  • It is hypothesized that depolarization or block of potassium channels allows recruitment of voltage-dependent calcium channels (VDCCs) and increased contraction. (americanasthmafoundation.org)
  • KCa2.3 is most abundant in regions of the brain, but has also been found to be expressed in significant levels in many other peripheral tissues, particularly those rich in smooth muscle, including the rectum, corpus cavernosum, colon, small intestine and myometrium. (wikipedia.org)
  • KCa2.3 channels play a major role in human physiology, particularly in smooth muscle relaxation. (wikipedia.org)
  • His studies demonstrated that chronic psychological stress profoundly disrupts inward-rectifier potassium channel-mediated neurovascular coupling, and revealed that the brain's capillary network constitutes a vast 'sensory web', capable of translating local neural activity into vasodilatory electrical signals. (umaryland.edu)
  • The authors used 2-photon microscopy to obtain high resolution images of calcium signals in the apical dendrites while activating Schaffer collateral inputs to induce long-term potentiation (LTP) of different durations. (yale.edu)
  • Tom was promoted to Assistant Professor in 2015 and continued to work on brain capillaries, with a focus on local endothelial calcium signaling which regulates blood flow through the deep capillary bed. (umaryland.edu)
  • These data suggest that endothelial TRPA1 channels are sensors of hypoxia leading to vasodilation, thereby reducing ischemic damage. (elifesciences.org)
  • This study demonstrates that, in Arabidopsis roots, exogenous l-ascorbic acid triggers a transient increase of the cytosolic free calcium activity ([Ca2+]cyt. (deepdyve.com)
  • Future studies will assess whether drugs that activate TRPA1 have the potential to help reduce long-term disabilities in human patients who have a stroke. (elifesciences.org)
  • In addition, using Western blotting, we sought to determine the level of protein expression of SK and IK channels in sensory nervous tissues following induction of inflammation (Freund's Complete Adjuvant (FCA) arthritis model) or nerve injury (chronic constriction injury model). (dundee.ac.uk)
  • These results are the first to demonstrate that metformin restored IK Ca - and SK Ca -mediated vasodilatation impaired by AGEs in rat mesenteric artery, in which the upregulation of channel activity and protein expression is likely involved. (aspetjournals.org)
  • The fast AHP component increases the availability of sodium channels, which facilitates the generation of burst discharge. (eneuro.org)
  • It belongs to a family of channels known as small-conductance potassium channels, which consists of three members - SK1, SK2 and SK3 (encoded by the KCNN1, 2 and 3 genes respectively), which share a 60-70% sequence identity. (wikipedia.org)
  • Very recently, the sequencing of the genes that code for SK, IK and BK channels has allowed a definition of the mechanisms of channel gating and of the participation of calmodulin in it. (conicyt.cl)
  • We studied modulation of glutamate-evoked calcium rises in primary astrocyte cultures using fura-2 ratiometric digital calcium imaging. (jneurosci.org)
  • Here, we review cellular mechanisms and signaling pathways involved in axonal ion channel modulation and examine how changes to ion channel function affect AP initiation, AP propagation, and the release of neurotransmitter. (frontiersin.org)
  • It was already known that GrC of vestibulo-cerebellum are specialized to slow-down firing modulation based on the expression of low-threshold Ca 2+ channels 27 . (nature.com)
  • Chemicals that inhibit the production of free radicals blocked the activity of the TRPA1 channels. (elifesciences.org)
  • Ca(2+)-activated K(+) channel-3.1 blocker TRAM-34 attenuates airway remodeling and eosinophilia in a murine asthma model. (harvard.edu)
  • These SK channels are abundant in the nervous system, where they mediate slow after-hyperpolarizations that modulate excitability. (conicyt.cl)
  • From a physiological and pathophysiological point of view, the conformational states of the sodium channel during heart function constitute a significant aspect for the diagnosis and treatment of heart diseases. (bvsalud.org)
  • Wulff H, Christophersen P, Colussi P, Chandy KG, Yarov-Yarovoy V. Antibodies and venom peptides: new modalities for ion channels. (ucdavis.edu)
  • For Ca increase in long duration LTP (LTP3), see Ca channels in CA1 pyramidal cell apical dendrite. (yale.edu)
  • The channel activity was observed using a whole-cell patch voltage clamp. (aspetjournals.org)
  • This process is mediated by a rich assortment of voltage-gated ion channels whose function can be affected on short and long time scales by activity. (frontiersin.org)
  • Cellular mechanisms of neuromodulation of axonal ion channels. (frontiersin.org)
  • however, the mechanisms that coordinate photosynthesis and stomatal conductance have yet to be identified. (nature.com)
  • This was better defined when recordings were made of single channels in many different preparations in combination with the use of selective blockers. (conicyt.cl)