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Colom L V - - 1998
Basal forebrain cholinergic neurons are severely depleted early in Alzheimer's disease and appear particularly susceptible to amyloid beta-peptide (A beta) toxicity in vivo. To model this effect in vitro, a cholinergic septal cell line (SN56) was exposed to A beta. SN56 cells exhibited a tetraethylammonium (TEA)-sensitive outward K+ current with ...
Relevancy Score: Relevancy Score: 258
Rodríguez-Navarro Alonso - - 2006
All living cells have an absolute requirement for K+, which must be taken up from the external medium. In contrast to marine organisms, which live in a medium with an inexhaustible supply of K+, terrestrial life evolved in oligotrophic environments where the low supply of K+ limited the growth of ...
Relevancy Score: Relevancy Score: 258
Hasin Y - - 1984
Interruption of synthesis of ATP during hypoxia or ischemia can produce membrane depolarization that may be related to inhibition of Na+-K+-ATPase. To examine this hypothesis, the effects of exposure of cultured chick embryo ventricular cells to 1 mM cyanide (CN), to 20 mM 2-deoxy-D-glucose (2-DG), to CN + 2-DG, and ...
Relevancy Score: Relevancy Score: 258
Vais H - - 1995
The effects of ryanodine, 9,21-didehydroryanodine and 9,21-didehydroryanodol on two types of K(+) channel (a maxi, Ca(2+)-activated, 170pS channel (BK channel) and an inward rectifier, stretch sensitive channel of 35 pS conductance (IK channel)found in the plasma membrane of locust skeletal muscle have been investigated. 10(-9) M-10(-5) M ryanodine irreversibly induced ...
Relevancy Score: Relevancy Score: 258
Malysz J - - 2001
PURPOSE: Cavernous smooth muscle cells have a key role in the control of penile erection and detumescence. In this study the types of smooth muscle cells and currents present in isolated rabbit corpus cavernosum myocytes were characterized. MATERIALS AND METHODS: Immunohistochemical methods were used to identify cavernous smooth muscle cells. ...
Relevancy Score: Relevancy Score: 258
Hertel Brigitte - - 2005
Structural analysis of K+ channel pores suggests that the selectivity filter of the pore is an inherent sensor for extracellular K+ (Ko+); channels seem to be inactivated at low Ko+ because of a destabilization of the conducting state and a collapse of the pore. In the present study, the effect ...
Relevancy Score: Relevancy Score: 258
Zakharov Sergey I - - 2005
Pharmacologic approaches to activate K+ channels represent an emerging strategy to regulate membrane excitability. Here we report the identification and characterization of a lipid soluble toxin, mallotoxin (rottlerin), which potently activates the large conductance voltage and Ca2+-activated K+ channel (BK) expressed in a heterologous expression system and human vascular smooth ...
Relevancy Score: Relevancy Score: 258
Gomora J C - - 1999
Bovine adrenal zona fasciculata cells express a novel K+ current (IAC) that sets the resting potential while it couples adrenocorticotropin and angiotensin II receptors to membrane depolarization and cortisol secretion. IAC is distinctive among K+ channels both in its activation by ATP and its inhibition by cyclic AMP. Whole-cell and ...
Relevancy Score: Relevancy Score: 258
Newman E A - - 1993
The voltage- and K(+)-dependent properties of Müller cell currents and channels were characterized in freshly dissociated salamander Müller cells. In whole-cell voltage-clamp experiments, cells with endfeet intact and cells missing endfeet both displayed strong inward rectification. The rectification was similar in shape in both groups of cells but currents were ...
Relevancy Score: Relevancy Score: 258
Colden-Stanfield M - - 1990
Bovine aortic endothelial cells (BAECs) respond to bradykinin with an increase in cytosolic-free Ca2+ concentration, [Ca2+]i, accompanied by an increase in surface membrane K+ permeability. In this study, electrophysiological measurement of K+ current was combined with 86Rb+ efflux measurements to characterize the K+ flux pathway in BAECs. Bradykinin- and Ca2(+)-activated ...
Relevancy Score: Relevancy Score: 258
Reddy M M - - 2006
Absorptive epithelial cells must admit large quantities of salt (NaCl) during the transport process. How these cells avoid swelling to protect functional integrity in the face of massive salt influx is a fundamental, unresolved problem. A special preparation of the human sweat duct provides critical insights into this crucial issue. ...
Relevancy Score: Relevancy Score: 258
Costa Alex - - 2004
The expression pattern of the KDC1 gene, coding for an inwardly-rectifying K(+) channel of Daucus carota , is described in several embryo stages and seedling tissues. Relative quantitative RT-PCR experiments indicated that, during (somatic) embryonic development, the KDC1 transcript appears as early as the globular stage and that the transcript ...
Relevancy Score: Relevancy Score: 258
Rusch N J - - 1994
Rat arterial muscle cells show an elevated Ca(2+)-dependent K+ efflux during the established phase of hypertension. This association of enhanced K+ efflux with high arterial pressure implies that changes of in vivo blood pressure can alter the level of K+ channel current in arterial membranes. We directly tested this hypothesis ...
Relevancy Score: Relevancy Score: 258
Piwnica-Worms D - - 1985
The polystrand preparation of cultured chick heart cells has a unidirectional transmembrane Cl- efflux that is twice K+ efflux. However, Cl- conductance of this heart cell membrane is low [regardless of extracellular K+ (K+o)], suggesting the existence of electroneutral Cl--dependent transport mechanisms. Furosemide (10(-3) M) decreases the 36Cl tracer efflux ...
Relevancy Score: Relevancy Score: 258
Ohya Susumu - - 2006
K+ channels play important roles in the control of a large variety of physiological functions such as muscle contraction, neurotransmitter release, hormone secretion, and cell proliferation. Over 100 cloned K+ channel pore-forming alpha and accessory beta subunits have been identified so far. Here, we introduce a series of molecular pharmacological ...
Relevancy Score: Relevancy Score: 258
Washburn D L - - 1999
The subfornical organ is one of a specialized group of CNS structures devoid of a significant blood-brain barrier, collectively known as the circumventricular organs. While peptides are normally excluded from access to most regions of the CNS, the subfornical organ contains neurons with a high density of receptors for many ...
Relevancy Score: Relevancy Score: 258
Clausen Torben - - 2010
Human skeletal muscles contain the largest single pool of K+ in the body (2600 mmol, 46 times the total K+ content of the extracellular space). Intense exercise may double arterial plasma K+ in one min. This is because of excitation-induced release of K+ from the working muscle cells via K+ ...
Relevancy Score: Relevancy Score: 258
Senn M E - - 2001
Plant K(+) transporters of the HAK family belong to four rather divergent phylogenetic clusters, although most of the transporters belong to clusters I or II. A simple phylogenetic analysis of fungal and plant HAK transporters suggests that an original HAK gene duplicated even before fungi and plants diverged, generating transporters ...
Relevancy Score: Relevancy Score: 258
Kettenmann H - - 1987
The K+ uptake processes of immunologically identified oligodendrocytes from embryonic mouse spinal cord were studied in primary culture by injecting ions and recording membrane potential changes and, in some experiments, K+ ion activity with intracellular electrodes. When Na+ was injected [K+]i decreased. Immediately before and after current injection the membrane ...
Relevancy Score: Relevancy Score: 258
Rosado J A - - 1997
In this study, K+ concentration was measured in effluent samples from superfused guinea-pig pancreatic pieces in control conditions and during stimulation with ACh, employing the technique of flame photometry. ACh (10(-7)-10(-5) M) evoked a dose-dependent and sustained increase in K+ concentration in the effluent (K+ release). The removal of Ca2+ ...
Relevancy Score: Relevancy Score: 258
Sandle G I - - 1999
Somatostatin is a powerful inhibitor of intestinal Cl(-) secretion. We used patch-clamp recording techniques to investigate the effects of somatostatin on low-conductance (23-pS) K(+) channels in the basolateral membrane of human colonic crypts, which are an important component of the Cl(-) secretory process. Somatostatin (2 microM) elicited a >80% decrease ...
Relevancy Score: Relevancy Score: 258
Pamnani M B - - 1991
Reports from several laboratories suggest the presence of an ouabainlike compound in plasma and various animal tissues, particularly during acute volume expansion and in low-renin hypertension. It has been hypothesized that this compound, through inhibition of the Na(+)-K+ pump, can constrict blood vessels, enhance vasoconstriction in response to agonists, increase ...
Relevancy Score: Relevancy Score: 258
Cowan C L - - 1993
Endothelium-dependent relaxation is associated with smooth muscle hyperpolarization in many arteries which may account for relaxation that persists in the presence of nitric oxide inhibitors such as NG-nitro-L-arginine methyl ester (L-NAME). Acetylcholine (ACh)-induced relaxations of the rabbit thoracic and abdominal aorta and iliac and carotid arteries were studied for the ...
Relevancy Score: Relevancy Score: 258
Satlin Lisa M - - 2004
PURPOSE OF REVIEW: Somatic growth is associated with an increase in total body K content. K homeostasis is regulated, in large part, by urinary K excretion. Within the adult kidney and specifically the cortical collecting duct, K secretion is accomplished by the passive diffusion of cell K into the urinary ...
Relevancy Score: Relevancy Score: 258
Cui Yijun - - 2002
Intracellular application of certain charged methanethiosulfonate (MTS) reagents modified and irreversibly inhibited Kir6.2 channels when cysteine substitutions were introduced at positions Ile-210, Ile-211, or Ser-212 within the putative cytoplasmic region. Inhibition depends on the spatial dimensions of the MTS reagents. Reaction of MTS reagents, having head diameters of 7.6-8.2 A, ...
Relevancy Score: Relevancy Score: 258
Veraldi Stefano S Department of Pathophysiology and Transplantation, University of Milan, I.R.C.C.S. Foundation, Cà Granda Ospedale Maggiore Policlinico, Milan, - - 2014
Abstract Thirty-seven adult Caucasian patients (9 males and 28 females), with erythemato-telangiectatic rosacea accompanied by stinging and burning sensation, were treated with a cream containing 5% potassium azeloyl diglycinate and 1% hydroxypropyl chitosan. All patients were previously treated at other centers with topical azelaic acid and/or metronidazole. The cream was ...
Relevancy Score: Relevancy Score: 258
Imbrici Paola - - 2013
Voltage-gated ion channels are important mediators of physiological functions in the central nervous system. The cyclic activation of these channels influences neurotransmitter release, neuron excitability, gene transcription, and plasticity, providing distinct brain areas with unique physiological and pharmacological response. A growing body of data has implicated ion channels in the ...
Relevancy Score: Relevancy Score: 258
Hulter H N - - 1980
In dogs dietary K+ restriction (16 days) results in diminished urinary net acid excretion (NAE) and systemic hyperchloremic metabolic acidosis (sigma delta NAE, -200 meq; delta[HCO3-]p, -2.9 +/- 0.3 meq/liter, P less than 0.05). Urinary aldosterone (aldo) excretion decreased by 34 +/- 3% (P less than 0.001) and metabolic clearance ...
Relevancy Score: Relevancy Score: 258
Ballmaier D - - 1995
The oxidative DNA damage induced by the renal carcinogen potassium bromate (KBrO3) in cultured mammalian cells and in a cell-free system was characterized by means of various repair endonucleases. Under cell-free conditions, no modifications were induced by KBrO3 alone, but extensive DNA damage was observed in the presence of glutathione ...
Relevancy Score: Relevancy Score: 258
Gámez P - - 2005
OBJECTIVE: Lung preservation quality is a crucial factor in the success of a lung transplant. In October 2000 we stopped using Euro-Collins (EC) lung preservation solution and began using a low potassium dextran solution (Perfadex [PER]). The objective of the present study was to assess outcome with the 2 solutions. ...
Relevancy Score: Relevancy Score: 258
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