Disease relevance of POTASSIUM

• Addition of saline-adenine-glucose solutions (40 to 100 ml per blood unit) to buffy-coat-poor red-cell concentrates allowed storage for as long as 35 days with 24-hour erythrocyte post-transfusion survival of 83 +/- 6.8 per cent (+/0 S.D.). Potassium leakage was lower, and in vitro hemolysis somewhat higher than that of whole blood [1].
• BACKGROUND: The efflux of potassium (K) through the ATP-sensitive K channel is considered an important cause of the rise in extracellular K ([K+]e) during no-flow ischemia [2].
• To study myocardial metabolism in chronic hypoxia due to cyanotic congenital heart disease, coronary arteriovenous differences of lactate (L), pyruvate (P), inorganic phosphate (Pi) and potassium (K) were measured in 14 cyanotic patients and seven controls, at rest and during atrial pacing [3].
• Familial pseudohyperkalemia is a "leaky red blood cell" condition in which the cells show a temperature-dependent loss of potassium (K) from red blood cells when stored at room temperature, manifesting as apparent hyperkalemia [4].
• The transient potassium (K+) current, or A-current (IA), plays an essential role in shaping the firing properties of identified neurons in the 14-cell pyloric network in the stomatogastric ganglion of the spiny lobster, Panulirus interruptus [5].

Psychiatry related information on POTASSIUM

• Several alterations in fibroblasts of Alzheimer's disease (AD) patients have been described, including alterations in calcium regulation, protein kinase C (PKC), and potassium (K+) channels [6].
• The aim of this study was to determine that hypokinesia (restricted motor activity) could increase potassium (K+) losses with decreased tissue K+ content showing decreased K+ deposition [7].

High impact information on POTASSIUM

• The Drosophila Shaker (Sh) gene appears to encode a type of voltage-sensitive potassium (K+) channel called the A channel [8].
• Depletion of intracellular potassium (K+) caused a marked reduction in the rate of endocytosis of receptor-bound low density lipoprotein (LDL) and epidermal growth factor (EGF) in human fibroblasts [9].
• The conserved motif in the Cl- channel P1 region may constitute a 'signature' sequence for an anion-selective ion pore by analogy with the homologous GYG sequence that is essential for selectivity in voltage-gated potassium ion (K+) channel pores [10].
• We demonstrate here that secretion of catecholamines evoked from the rat adrenal gland by stimulation of splanchnic nerves, excess potassium (K+) and nicotine is facilitated by phorbol 12,13-dibutyrate [11].
• Repolarization of the action potential in squid axon1 and several types of neurones2-4 involves a voltage-activated potassium (K+) current [12].

Chemical compound and disease context of POTASSIUM

• In the present study, we measured the intracystic levels of sodium (Na+), potassium (K+), dehydroepiandrosterone-sulphate (DHEA-S), and epidermal growth factor (EGF), a factor which could play a role in the autocrine or paracrine control of breast cancer cell growth as recently proposed by some investigators [13].
• Cisplatin is a common cause of hypomagnesemia and hypokalemia due to renal magnesium (Mg) and potassium (K) losses [14].
• AIMS: To assess the anti-ischaemic and anti-arrhythmic effects and overall safety of nicorandil, an ATP sensitive potassium (K+) channel opener, with 'cardioprotective' effects, in patients with unstable angina [15].
• Diazepam pretreatment prevented muscle fasciculations, increases in serum potassium (K+) and creatinine phosphokinase (CPK) levels, increased heart rate and arterial pressure, and postoperative myalgia associated with SCh administration [16].
• BACKGROUND: Potassium citrate is commonly used in combination with a thiazide diuretic in the medical management of recurrent hypercalciuric nephrolithiasis [17].

Biological context of POTASSIUM

• Inwardly rectifying potassium (K+) channels (IRKs) maintain the resting membrane potential of cells and permit prolonged depolarization, such as during the cardiac action potential [18].
• Histidine Phosphorylation of the Potassium Channel KCa3.1 by Nucleoside Diphosphate Kinase B Is Required for Activation of KCa3.1 and CD4 T Cells [19].
• (g) Potassium receptors, either demonstrated or inferred, initiate reflex increases in respiration, heart rate, blood pressure, and peripheral tissue potassium uptake as well as a reflex inhibition of skeletal muscle ion pumps [20].
• There is considerable evidence that the central nervous system (CNS) is significantly involved in potassium homeostasis: (a) Potassium-specific receptors located in the liver or hepatic portal circulation initiate a reflex increase in potassium excretion via vagal afferents [20].
• Relying on the ability of functional KAT1 channels to rescue potassium (K+) transport-deficient yeast, we have performed an unbiased mutagenesis screen aimed at determining whether S4 packs against S5 of the pore domain [21].

Anatomical context of POTASSIUM

• Both serotonin and the selective gamma-aminobutyric acidB (GABAB) agonist, baclofen, increase potassium (K+) conductance in hippocampal pyramidal cells [22].
• The role of apical and basolateral membranes in aldosterone-induced active potassium (K) secretion in rat distal colon was investigated by measuring mucosal-to-serosal (Jms) and serosal-to-mucosal (Jsm) 42K fluxes (mueq.h-1.cm-2) across isolated stripped mucosa under short-circuit conditions in normal and secondary-hyperaldosterone animals [23].
• We have confirmed that phytohemagglutinin (PHA) rapidly enhances the uptake of potassium (K+) by human blood lymphocytes [24].
• The primary effect of AII is activation of phospholipase C, which increases both calcium release from intracellular stores and calcium flux across the cell membrane and activates protein kinase C. Potassium depolarizes the membrane, thereby activating calcium flow through voltage-dependent calcium channels [25].
• Potassium ion influx and Na+,K+-ATPase activity are required for the hamster sperm acrosome reaction [26].

Associations of POTASSIUM with other chemical compounds

• Parasympathetic slowing of the heart rate is predominantly mediated by acetylcholine-dependent activation of the G protein-gated potassium (K+) channel (IK,ACh) [27].
• The amino acid change occurred in the eighth alpha helix of A domain (A alpha 8) of PK, and it has been proposed that this region as well as A alpha 7, A beta 7, and A beta 8 is a potassium (K+) binding site [28].
• Normal human red blood cells, when exposed briefly to acetylphenylhydrazine (APH), acquire Heinz bodies and a propensity for net ion and water loss upon subsequent incubation in an APH-free medium of physiologic sodium and potassium (K) content [29].
• The present study examined the role of two CRCP families-CPP32- and interleukin-1beta converting enzyme (ICE)-like cysteine proteases-in apoptosis of cerebellar granule cells (CGCs) caused by withdrawal of serum and/or potassium (K+) [30].
• Tyrosine Phosphatases {varepsilon} and {alpha} Perform Specific and Overlapping Functions in Regulation of Voltage-gated Potassium Channels in Schwann Cells [31].

Gene context of POTASSIUM

• Mutations in the KCNQ1 gene, which encodes the cardiac KvLQT1 potassium ion (K+) channel, cause both the autosomal dominant Romano-Ward (RW) syndrome and the recessive Jervell and Lange-Nielsen (JLN) syndrome [32].
• To date, two voltage-gated potassium (K+) channel genes, KCNQ2 and KCNQ3, have been identified in typical BNFC families [33].
• Isolation, mapping, and sequencing of trapped exons and captured cDNAs from cosmids of this region have revealed the presence of a gene (KCNJ15) encoding a potassium (K+) channel belonging to the family of inward rectifier K+ (Kir) channels [34].
• Two neurological mutants deafwaddler (dfw) and opisthotonos (opt) and a cluster of three Shaker-like potassium (K) channel genes Kcna1, Kcna5, and Kcna6 were all independently mapped to distal mouse chromosome six (Chr 6) [35].
• OBJECTIVE: Potassium (K(+)) channels on immune cells have gained attention recently as promising targets of therapy for immune-mediated neurological diseases such as multiple sclerosis (MS) [36].

Analytical, diagnostic and therapeutic context of POTASSIUM

• Potassium ion depletion filter for blood transfusion [37].
• Using the whole-cell variation of the patch-clamp technique, we found a voltage-dependent potassium (K+) current in NK cells [38].
• The extracellular and intracellular potassium (K+) activities of isolated superfused rabbit atrial muscle were measured using K+-sensitive liquid ion exchanger microelectrodes [39].
• To determine whether this phenomenon is due to a disturbance in factors that stimulate ALDO, we measured PRA, angiotensin II (AII), potassium (K+), and ACTH levels in 83 patients admitted to an intensive care unit [40].
• The PK/PD analysis indicated that the baseline QTc interval was dependent on gender, New York Heart Association Class, digoxin, and paced artificial pacemaker spike, whereas the 50% effective concentration (EC(50)) was dependent on the serum potassium (K) level, where EC(50) = 107 x K [41].

References