Inwardly rectifying potassium channels mediate. Medical search. Frequent questions

Phentolamine block of KATP channels is mediated by Kir6.2. (ox.ac.uk)
The beta cell KATP channel is a complex of two proteins: Kir6.2 and SUR1. (ox.ac.uk)
The former is an ATP-sensitive K+-selective pore, whereas SUR1 is a channel regulator that endows Kir6.2 with sensitivity to sulfonylureas. (ox.ac.uk)
We have used a truncated form of Kir6.2, which expresses independently of SUR1, to show that phentolamine does not inhibit KATP channels by interacting with SUR1. (ox.ac.uk)
Instead, our results argue that phentolamine may interact directly with Kir6.2 to produce a voltage-independent reduction in channel activity. (ox.ac.uk)
Our results suggest that this may be because Kir6.2, which is expressed in the heart, forms the pore of the cardiac KATP channel. (ox.ac.uk)
Rat inwardly rectifying potassium channel Kir6.2: cloning electrophysiological characterization, and decreased expression in pancreatic islets of male Zucker diabetic fatty rats. (uchicago.edu)
Membrane areas excised from COS cells cotransfected with Kir6.2-SUR1 or Kir6.2?C37-SUR1 exhibited single-channel activity quality of pancreatic KATP stations. (immune-source.com)
Kir6.2?C37 alone formed functional stations with single-channel conductance and intraburst kinetic properties comparable to those of Kir6.2-SUR1 or Kir6.2?C37-SUR1 but with minimal burst duration. (immune-source.com)
Specifically, current through recombinant wild-type SUR1/Kir6.2 channels expressed in COS7 cells was activated by NO, but channels formed only from truncated isoform Kir6.2 subunits without SUR1 subunits were insensitive to NO. Further, mutagenesis of SUR1 indicated that NO-induced K ATP channel activation involves interaction of NO with residues in the NBD1 of the SUR1 subunit. (biomedcentral.com)
K ATP channels, widely represented in metabolically active tissues, are hetero-octamers composed of four regulatory SUR subunits (SUR1, SUR2A, or SUR2B) and four ATP-sensitive pore-forming inwardly rectifying potassium channel (Kir6.x) subunits (Kir6.1 or Kir6.2) [ 20 ]. (biomedcentral.com)

The effects of melatonin on circadian pacemaker activity in the central nervous system may be the result of melatonin receptor activation of G-protein coupled potassium channels which inhibit the action potential firing of neurons. (elsevierpure.com)
Previously, CB1 receptors have been shown to inhibit D1 receptor-mediated cAMP accumulation ( Bidaut-Russell and Howlett, 1991 ). (jneurosci.org)
Zhang DY, Wu W , Deng XL, Lau CP, Li GR. Genistein and tyrphostin AG556 inhibit inwardly-rectifying Kir2.1 channels expressed in HEK 293 cells via protein tyrosine kinase inhibition. (ucsd.edu)

The ATP-sensitive K+-channel (KATP channel) plays a key role in insulin secretion from pancreatic beta cells. (ox.ac.uk)
Aldosterone, by inducing renal reabsorption of sodium at the distal convoluted tubule (DCT), enhances secretion of potassium and hydrogen ions, causing hypernatremia, hypokalemia, and alkalosis. (medscape.com)

The G protein-coupled inwardly rectifying potassium channels (GIRKs) are a family of lipid-gated inward-rectifier potassium ion channels which are activated (opened) by the signaling lipid PIP2 and a signal transduction cascade starting with ligand-stimulated G protein-coupled receptors (GPCRs). (wikipedia.org)
Examples of GIRKs include a subset of potassium channels in the heart, which, when activated by parasympathetic signals such as acetylcholine through M2 muscarinic receptors, causes an outward current of potassium, which slows down the heart rate. (wikipedia.org)
10 Furthermore, in the MOR-1 knockout mouse, morphine does not induce antinociception demonstrating that at least in this species morphine's analgesia is not mediated through d - or k -receptors. (opioids.wiki)
Altogether, the presented study provides a new insight into the involvement of the GABA-ergic system in the rewarding effects of mephedrone, implying that those effects are at least partially mediated through GABAB receptors, which suggests their potential role as new targets for the pharmacological management of mephedrone use disorder. (bvsalud.org)
As for postsynaptic https://ecosoberhouse.com/ B receptors, they could induce slow IPSP by activating outward potassium channels and suppressing inward HVA calcium channels. (dentistasbenicarlo.com)
Besides, extra-synaptic GABAB receptors, as well as other G protein-coupled receptors, could activate LVA Ca channels to induce neuronal oscillation, though part of LVA calcium channels normally remain silent. (dentistasbenicarlo.com)
Xenopus laevis and human(1a) melatonin receptors stimulated heteromeric G-protein activated inwardly rectifying potassium channels (Kir3.1/Kir3.2) when expressed in vitro in oocytes. (elsevierpure.com)
Both of these effects occur via postsynaptic A1 receptors, but are mediated downstream by two separate mechanisms. (nih.gov)
Pertussis toxin treatment of striatal neurons prevented the inhibition of cAMP accumulation by D2 receptors but unmasked a cannabinoid receptor-mediated stimulatory effect on cAMP accumulation. (jneurosci.org)
Other downstream effectors of Gα(i/o)-coupled receptors, G protein-coupled inwardly rectifying potassium channels and adenylate cyclase, were not modulated by GPR18 signaling. (unboundmedicine.com)

Finally, the Gβγ dimeric protein interacts with GIRK channels to open them so that they become permeable to potassium ions, resulting in hyperpolarization of the cell membrane. (wikipedia.org)
G protein-coupled inwardly rectifying potassium channels are a type of G protein-gated ion channels because of this direct interaction of G protein subunits with GIRK channels. (wikipedia.org)
and (c) a direct TA1 receptor-mediated activation of GIRK channels which produce cell membrane hyperpolarization. (wikipedia.org)
Furthermore, at higher concentrations, CGP7930 also blocks G protein-coupled inwardly-rectifying K+ (GIRK) channels diminishing GABABR signalling in HEK 293 cells. (bvsalud.org)
In conclusion, our study of CGP7930 modulation of GABAARs, GABABRs and GIRK channels, indicates this compound is unsuitable for use as a specific GABABR PAM. (bvsalud.org)
In the heart, the atrial G protein regulated inwardly rectifying potassium (GIRK) channels participate in the autonomic control of heart rate. (cognistrata.org)
This work revealed for the first time the complex language used by the GIRK channels in the translation of a simple message of the autonomic nervous system into miniature electrical currents. (cognistrata.org)
This work investigated the correlation between the intensity of the chemical signal (in this case, the concentration of free G protein in the membrane) and the complex language of the GIRK channel. (cognistrata.org)
Based on our findings, we developed the first model of regulation of GIRK channels by G proteins. (cognistrata.org)
This work tested the idea that the individual GIRK channels are enveloped into a network of signaling proteins in the membrane of cardiac cells and the channel activity reports not only the intensity of the chemical signals, but also the activation state of the rest of the proteins in the GIRK signaling network. (cognistrata.org)
This idea led to the purification of the cardiac signaling network and to identification of GIRK channel signaling partners. (cognistrata.org)
Nikolov, E.N., & Ivanova-Nikolova, T.T. "Functional characterization of a small conductance GIRK channel in rat atrial cells. (cognistrata.org)
This work characterized a previously unknown GIRK channel in the heart that together with the traditional GIRK channels controls the heart rate. (cognistrata.org)
The regulation of the newly identified GIRK channels by G proteins, like the regulation of the traditional GIRK channels, reflected the state of activation of the additional signaling components in the membrane network. (cognistrata.org)
Nikolov, E.N., & Ivanova-Nikolova, T.T. "Dynamic integration of α-adrenergic and cholinergic signals in the atria: Role of GIRK channels. (cognistrata.org)

Martin (1967) concluded that the analgesic action of nalorphine is mediated by a receptor, later called the k -opioid receptor, that is different from the morphine receptor. (opioids.wiki)
Ethanol's CNS actions are mediated through many receptor types, including GABA-A, NMDA, glycine, and G-protein-activated inwardly rectifying potassium channels. (dentistasbenicarlo.com)
This suggests a potential role for heteromeric Kir3 channels in the receptor-mediated actions of melatonin in vivo. (elsevierpure.com)
Treatment of the pertussis toxin-treated cells with cholera toxin before CB1 receptor activation amplified the stimulatory pathway, suggesting that this response was mediated through a G s -type G-protein. (jneurosci.org)
Opioids close N-type voltage-operated calcium channels (OP2-receptor agonist) and open calcium-dependent inwardly rectifying potassium channels (OP3 and OP1 receptor agonist). (pharmfair.com)
New insights into the mechanisms underlying AF have identified promising new approaches, including the modulation of atrium-specific ion channels, connexins and the ryanodine receptor, the prevention of remodelling processes that lead to the arrhythmia as well as specific molecular events involved in arrhythmia generation. (nature.com)
Inhibition of cell proliferation by the somatostatin analogue RC-160 is mediated by somatostatin receptor subtypes SSTR2 and SSTR5 through different mechanisms. (uchicago.edu)
Gi alpha 1 selectively couples somatostatin receptor subtype 3 to adenylyl cyclase: identification of the functional domains of this alpha subunit necessary for mediating the inhibition by somatostatin of cAMP formation. (uchicago.edu)

The Swarm was able to record pseudo-action potentials stably across all 24 objectives and provided pharmacological characterization of diverse sodium channel blockers. (frontiersin.org)
Characterization of SKT1, an inwardly rectifying potassium channel from potato, by heterologous expression in insect cells. (mpg.de)

The pancreatic -cell ATP-sensitive potassium (KATP) channel is a multimeric protein complex made up of four inwardly rectifying potassium channel (Kir6. (thetechnoant.info)
Structurally unique among ion channels ATP-sensitive K+ (KATP) channels are crucial in coupling cellular metabolism with membrane excitability and their activity could be reconstituted simply by coexpression of the inwardly rectifying K+ channel Kir6. (immune-source.com)

Widagdo J, Anggono V, Wong JJ (2022) The multifaceted effects of YTHDC1-mediated nuclear m6A recognition. (anggonolab.org)

These are called muscarinic potassium channels (IKACh) and are heterotetramers composed of two GIRK1 and two GIRK4 subunits. (wikipedia.org)
Ivanova-Nikolova, T.T. and Breitwieser, G.E. "Effector contributions to Gβγ-mediated signaling as revealed by muscarinic potassium channel gating. (cognistrata.org)

Channel properties are modulated by cAMP and subunit assembly. (scbdd.com)
Association of plant K-in(+) channels is mediated by conserved C-termini and does not affect subunit assembly. (mpg.de)

In male and female rat hippocampal neuron cultures, CGP7930 allosteric effects on GABAARs caused prolonged rise and decay times and reduced the frequency of inhibitory postsynaptic currents and potentiated GABAAR-mediated tonic inhibition. (bvsalud.org)
Cell-attached and cell-free recordings of K ATP currents in large DRG neurons from control rats (sham surgery, SS) revealed activation of K ATP channels by NO exogenously released by the NO donor SNAP, through decreased sensitivity to [ATP]i. (biomedcentral.com)
Failure to block the NO-mediated amplification of K ATP currents with specific inhibitors of sGC and PKG indicated that the classical sGC/cGMP/PKG signaling pathway was not involved in the activation by SNAP. (biomedcentral.com)
Dow-regulation of inwardly rectifying K + currents in astrocytes derived from patients with Monge's disease. (ucsd.edu)

This research provides direct proof an inwardly rectifying K+ route and an ATP-binding cassette proteins in physical form associate which impacts the mobile distribution and kinetic behavior of the KATP route. (immune-source.com)

This gene encodes an inwardly rectifying K+ channel which may be blocked by divalent cations. (nih.gov)
Wu W , Dong MQ, Wu XG, Sun HY, Tse HF, Lau CP, Li GR. Human ether-à-go-go gene potassium channels are regulated by EGFR tyrosine kinase. (ucsd.edu)

KATP channels also are found in the heart where they are involved in the response to cardiac ischemia: they also are blocked by phentolamine. (ox.ac.uk)

A reduction in the expression of large-conductance calcium-activated potassium (BK) channels and Kv3.3 voltage-gated potassium channels accompanies the inability of Purkinje neurons early in disease to maintain repetitive spiking. (elsevierpure.com)
Increased activity of K ir channels results in the generation of a novel AHP not seen in wild-type Purkinje neurons that also accounts for the reduced firing frequency late in disease. (elsevierpure.com)
ATP-sensitive potassium (K ATP ) channels in neurons regulate excitability, neurotransmitter release and mediate protection from cell-death. (biomedcentral.com)
Furthermore, activation of K ATP channels is suppressed in DRG neurons after painful-like nerve injury. (biomedcentral.com)
Therefore, we investigated NO modulation of K ATP channels in control and axotomized DRG neurons. (biomedcentral.com)
NO activates K ATP channels in large DRG neurons via direct S-nitrosylation of cysteine residues in the SUR1 subunit. (biomedcentral.com)
GPR18 was heterologously expressed in rat sympathetic neurons, and the modulation of N-type (Ca(v)2.2) calcium channels was examined. (unboundmedicine.com)

Optogenetic assays provide a flexible, scalable, and information rich approach to probe compound effects for ion channel drug targets in both heterologous expression systems and associated disease relevant cell types. (frontiersin.org)

Plant K+ channel alpha-subunits assemble indiscriminately. (mpg.de)

Zhang YH, Wu W , Sun HY, Deng XL, Cheng LC, Li X, Tse HF, Lau CP, Li GR. Modulation of human cardiac transient outward potassium current by EGFR tyrosine kinase and Src-family kinases. (ucsd.edu)

This protein is thought to be one of multiple inwardly rectifying channels which contribute to the cardiac inward rectifier current (IK1). (nih.gov)
The syndrome is caused by changes in the structure and function of certain cardiac ion channels and reduced expression of Connexin 43 (Cx43) in the Right Ventricle (RV), predominantly in the Right Ventricular Outflow Tract (VSVD), causing electromechanical abnormalities. (bvsalud.org)

Xiao GS, Zhang YH, Wu W , Sun HY, Wang Y, Li GR. Genistein and tyrphostin AG556 decrease human atrial ultra-rapidly activating delayed rectifier potassium current by inhibiting EGFR tyrosine kinase. (ucsd.edu)

However, the neuronal phenotype mediating these effects is unknown. (nih.gov)
Adenosine (0.5-100 microM) reduced the magnocellular preoptic nucleus and substantia innominata cholinergic neuronal firing rate by activating an inwardly rectifying potassium current that reversed at -82 mV and was blocked by barium (100 microM). (nih.gov)

These results suggest that the basis for spiking abnormalities in SCA2 differ depending on disease stage, and interventions targeted towards correcting potassium channel dysfunction in ataxia need to be tailored to the specific stage in the degenerative process. (elsevierpure.com)

Rise and Fall of Kir2.2 Current by TLR4 Signaling in Human Monocytes: PKC-Dependent Trafficking and PI3K-Mediated PIP2 Decrease. (nih.gov)
The capacity of NO to activate K ATP channels via this mechanism remains intact even after spinal nerve ligation, thus providing opportunities for selective pharmacological enhancement of K ATP current even after decrease of this current by painful-like nerve injury. (biomedcentral.com)

CYP2D6 mediates the biotransformation to morphine. (pharmfair.com)

The single-channel conductance is unaffected. (ox.ac.uk)
Wu W , Sun HY, Deng XL, Li GR. EGFR Tyrosine kinase regulates small conductance Ca 2+ -activated K + (hSKCa1) channels expressed in HEK 293 cells. (ucsd.edu)

This increase in gain presumably enhances visually mediated behaviors such as the active regulation of forward speed, a process that involves the comparison of a vision-based estimate of velocity with an internal set point. (silverchair.com)

Recent studies show that modulation of TASK-1 channels, either directly or indirectly by targeting their regulatory mechanisms, has the potential to control pulmonary arterial tone in humans. (ersjournals.com)

To evaluate the Swarm screening system, we optimized a series of heterologous optogenetic spiking HEK293 cell assays for several voltage-gated sodium channel subtypes including Nav1.2, Nav1.5, and Nav1.7. (frontiersin.org)

Mediates the rapidly activating component of the delayed rectifying potassium current in heart (IKr). (scbdd.com)
This review summarises our current state of knowledge of the functional role of TASK-1 channels in the pulmonary circulation in health and disease, with special emphasis on current advancements in the field. (ersjournals.com)
The headstage also provides an integrated stimulator, which can generate current or voltage stimulation signals on three independent channels (two for MEA2100-256-Systems) per MEA slot. (multichannelsystems.com)

Knockdown of inwardly rectifying potassium channel Kir2.2 suppresses tumorigenesis by inducing reactive oxygen species-mediated cellular senescence. (nih.gov)
Because their opening is determined by the cytosolic ADP/ATP ratio, K ATP channels act as metabolic sensors, linking cytosolic energetics with cellular functions in various tissues [ 21 , 22 ]. (biomedcentral.com)

NO-dependent mechanisms modulate both K ATP channels and participate in the pathophysiology and pharmacology of neuropathic pain. (biomedcentral.com)

Isoforms USO have no channel activity by themself, but modulates channel characteristics by forming heterotetramers with other isoforms which are retained intracellularly and undergo ubiquitin-dependent degradation. (scbdd.com)

Wu W , Wang Y, Deng XL, Sun HY, Li GR. Cholesterol down-regulates BK channels stably expressed in HEK 293 cells. (ucsd.edu)

Sodium-chloride (NaCl) enters the cell via the apical thiazide-sensitive NCC and leaves the cell through the basolateral Cl− channel (ClC-Kb), and the Na+/K+-ATPase. (medscape.com)

Other findings indicated that the mechanisms by which NO activates K ATP channels involve direct S-nitrosylation of cysteine residues in the SUR1 subunit. (biomedcentral.com)

Hypokalemia is generally defined as a serum potassium level of less than 3.5 mEq/L (3.5 mmol/L). Severe hypokalemia is a level of less than 2.5 mEq/L. Hypokalemia is a potentially life-threatening imbalance that may be iatrogenically induced. (medscape.com)

Figure 1: General mechanisms of AF and role of ion channels for AF stabilization. (nature.com)

The activation likely works by increasing the affinity of the channel for PIP2. (wikipedia.org)
Molecular basis of plant-specific acid activation of K+ uptake channels. (mpg.de)
This NO-induced K ATP channel activation was not altered in ganglia from animals that demonstrated sustained hyperalgesia-type response to nociceptive stimulation following spinal nerve ligation. (biomedcentral.com)
However, baseline opening of K ATP channels and their activation induced by metabolic inhibition was suppressed by axotomy. (biomedcentral.com)
NO-induced activation of K ATP channels remained intact in cell-free patches, was reversed by DTT, a thiol-reducing agent, and prevented by NEM, a thiol-alkylating agent. (biomedcentral.com)

TWIK-related acid-sensitive potassium channel 1 (TASK-1 encoded by KCNK3) belongs to the family of two-pore domain potassium channels. (ersjournals.com)
Ginsenoside Rg3, a gating modifier of EAG family K + channels. (ucsd.edu)

TASK-1 channels are sensitive to a wide array of physiological and pharmacological mediators that affect their activity such as unsaturated fatty acids, extracellular pH, hypoxia, anaesthetics and intracellular signalling pathways. (ersjournals.com)
In spite of a continued impairment in spike repolarization and a persistently reduced BK channel mediated afterhyperpolarization (AHP), repetitive spiking is maintained, through the increased activity of barium-sensitive potassium channels, most consistent with inwardly rectifying potassium(K ir ) channels. (elsevierpure.com)

Altered expression of genes for Kir ion channels in dilated cardiomyopathy. (nih.gov)

In high concentration PIP2 activates the channel absent G-protein, but G-protein does not activate the channel absent PIP2. (wikipedia.org)

12 The intake of taurine by energy drinks (1 L energy drink contains on average 3180 mg/L) exceeds by far the mean daily intake from omnivore diets (58 mg). 2 Consequently, there is growing concern about possible adverse effects mediated by taurine due to excessive energy drink consumption. (researchgate.net)

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Kir6.211

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Receptors10

GIRK15

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Kir62

20221

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Proteins1

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KATP1

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