PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Chloride Ion Level”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 55 records · Page 3Linked to original sources
PubMed1984

Endocrine physiology of electrolyte metabolism.

Historically, the sodium ion has been given prominence in relation to cardiovascular disease, perhaps to the exclusion of other ions. Recently, other ions, including chloride, potassium, magnesium and calcium have received increasing attention in relation to hypertension, cardiac arrhythmias, and metabolic derangements. Endocrine factors controlling these ions have also received increasing attention; they include classic hormonal actions as well as neurotransmission and paracrine hormonal actions. Studies indicate that control of the renin-angiotensin-aldosterone system resides in cytosolic calcium ion levels in the juxtaglomerular cell, as well as chloride ion and prostaglandins at the macula densa. Renin release is stimulated by hyperpolarisation of the juxtaglomerular cell induced by beta 1-agonists, parathyroid hormone, glucagon, magnesium and low cytosol calcium. Renin release is inhibited by high calcium, potassium and angiotensin II. Subsequent to renin release, hormonal regulation includes stimulation of converting enzyme activity by cortisol and prostaglandin (PGE2). Other hormonal control includes antidiuretic hormone producing dilution of extracellular electrolytes and augmented peripheral resistance. A recently identified natriuretic factor isolated from cardiac atria appears to be a potent diuretic with actions similar to that of frusemide (furosemide). Other electrolytes have received closer scrutiny. Chloride may play a dominant role in renal sodium reabsorption, responding to prostaglandin levels. Calcium has been recognised as a basic regulator of the secretion of such hormones as noradrenaline, renin, and aldosterone. As well, calcium ion changes are the means by which smooth muscle contraction is effected. Parathyroid hormone and vitamin D regulate the level of this ion in the body. In addition, a high dietary calcium intake appears to play a protective role against hypertension, while calcium channel blockers appear to reduce blood pressure. Endocrine systems play a major role in the protection against acute elevations in serum potassium by means of insulin action and adrenergic modulation of extrarenal potassium disposal. Aldosterone is recognised as the delayed regulator of potassium excretion. Magnesium levels fall in hyperaldosteronism, hyperparathyroidism, and diabetic keto-acidosis, as well as in malnutrition states. A coexisting potassium deficiency may be refractory to therapy until hypomagnesaemia is corrected. The integrated action of these hormones and electrolytes are thus of major importance in regulation of the cardiovascular system.

Adrenal Cortex Hormones↗
PubMed2002

Complexities in ETS-domain transcription factor function and regulation: lessons from the TCF (ternary complex factor) subfamily. The Colworth Medal Lecture.

The ETS-domain transcription factor family can be divided into a series of subfamilies. Elk-1 represents the founding member of the ternary complex factor (TCF) subfamily. By focusing on the TCF subfamily, we can demonstrate the complexities that exist in the function and regulation of ETS-domain transcription factors. This article focuses on Elk-1 in detail and summarizes the functions of other TCFs. The key themes covered include the domain structure of the TCFs, the mechanisms of complex formation with serum response factor, regulation of TCFs by mitogen-activated protein kinase cascades, and transcriptional regulatory properties of the TCFs. Finally, the emerging role of the TCFs in vivo is discussed. A picture is developing indicating that, while these proteins exhibit significant sequence and functional conservation, key differences in their structure and regulation are being identified which may relate to unique functions of these proteins in vivo.

Amino Acid Sequence↗
PubMed1982

The role of chloride ion in platelet serotonin transport.

Chloride ion is required for platelet serotonin transport. This anion requirement is relatively specific for Cl-. Only Br- fully substitutes, while SCN-, NO2-, and NO3- are much less effective. Serotonin influx requires external Cl-, and efflux requires internal Cl-. Although internal Cl- is not required for transport and has little effect on the initial rate of influx, it decreases the steady state level of serotonin accumulation. Chloride ion does not merely fulfill a need for a permanent ion since it is required for exchange of internal with external serotonin. Moreover, serotonin accumulation still requires external Cl- when a K+ diffusion potential (interior negative) is imposed across the vesicle membrane with valinomycin. Furthermore, Cl- lowers the Km and raises the Vmax for transport, suggesting direct effects on the transporter. These results strongly suggest serotonin-Cl- co-transport across the platelet plasma membrane.

Animals↗
PubMed1993

GABA-gated chloride ion influx in brains of tremor rats.

We measured the GABA-gated chloride ion influx and GABA concentrations in the cerebral cortex and the hippocampus of young (5 weeks old) and older (15 weeks old) tremor rats. GABA-gated chloride ion influx in these tremor rats was significantly greater than in the controls of both the 5 week- and 15 week-old groups. GABA concentrations in the cerebral cortex and hippocampus of the tremor rats increased compared with controls of 5 weeks and decreased compared with controls of 15 weeks. These findings suggest that the GABAergic presynaptic neurons in the cortex and hippocampus of the tremor rat are disturbed with aging. This change may be related to the appearance of absence-like seizures in the rats. The increased GABA-gated chloride ion influx in tremor rats may be a compensatory mechanism against the genetically-determined seizure susceptibility of these rats. Furthermore, the increased GABA levels and GABA-gated chloride ion influx found in 5 week-old tremor rats may be related to the tremor movements.

Animals↗
PubMed2006

Regioselective organocatalysis: a theoretical prediction of the selective rate acceleration of the SN2 reaction between an acetate ion and primary alkyl chlorides in DMSO solution.

High level ab initio calculations, including the solvent effect through a continuum solvation model, predict that 1,4-benzenedimethanol is able to catalyse the S(N)2 reaction between an acetate ion and primary alkyl chlorides in dimethyl sulfoxide solution. The catalysis takes place through two selective hydrogen bonds to the transition state. However, for secondary alkyl chlorides the catalysis is not effective due to steric repulsion and desolvation. This effect induces regioselective control of S(N)2 esterification reactions.

Journal Article↗
PubMed1988

Long-term effects of bleached kraft mill effluents on red and white blood cell status, ion balance, and vertebral structure in fish.

In a laboratory investigation fourhorn sculpin (Myoxocephalus quadricornis) were exposed for 5-9 months to wastewater from pine and birch lines from a bleached kraft pulp plant. This long-term exposure to bleached kraft mill effluent (BKME) affected the hematology, the ion balance, and the vertebral structure. Decreased values for hematocrit and hemoglobin and a reduced red blood cell count, as well as increased levels of methemoglobin, indicated disturbances in the red blood cell status. The white blood cell picture was not significantly affected by the BKME exposure. Decreased levels of potassium and chloride ions in the blood plasma in some of the exposed fish suggest an impaired ability to maintain ion homeostasis. Elevated frequencies of vertebral deformations in fish exposed to BKME confirm previous observations of vertebral damage in feral fourhorn sculpin caught in the receiving body of water of the same bleached kraft pulp industry. Many of the parameters analyzed in this investigation may be used as health indicators in future laboratory and field studies on fish exposed to BKME.

Animals↗
PubMed1992

Effects of chronic and in utero treatment with diuretics on mouse exocrine cells studied by X-ray microanalysis.

In an attempt to develop an animal model for the disease cystic fibrosis, mice were chronically treated with diuretics. In addition, pregnant mice were treated with diuretics and the effect of this treatment in utero on the newborn mice was studied. Pancreas and submandibular gland acinar cells were investigated by X-ray microanalysis and transmission electron microscopy. Long-term treatment with furosemide (up to 13 months) caused transient changes in the elemental content of the pancreatic acinar cells: a decrease in chloride and sulfur, and an increase in phosphorus, potassium and magnesium. All changes normalized with prolonged treatment. Some morphological changes were found in the zymogen granules. Treatment with amiloride or furosemide in utero caused a decrease in cellular sodium and chloride levels, indicative of inhibition of transepithelial ion and fluid transport. Also treatment of adult animals for two months with amiloride caused lower intracellular sodium and chloride levels. In adult animals only minor effects of diuretic treatment on submandibular gland acinar cells were noted. In utero treatment with amiloride caused an increase in sodium and chloride content indicative of cell damage.

Amiloride↗
PubMed1999

Kinetic parameters for dimeric and tetrameric forms of bovine dopamine beta-monooxygenase and their relationship to non-Michaelis-Menten behavior.

Bovine dopamine beta-monooxygenase has been assayed over a 10,000-fold range in protein concentration, to approximate conditions where the enzyme was shown to be a dimer or tetramer. Michaelis-Menten kinetics are observed with k(cat) and k(cat)/Km for dissociated enzyme reduced 30% and 200-300% relative to tetramer. Addition of chloride ions to very dilute enzyme or the use of intermediate enzyme concentrations causes non-Michaelis-Menten behavior, attributed to an equilibration between dimer and tetramer. This is not expected to contribute to activity within the chromaffin vesicle, where enzyme and chloride ions are at high levels.

Animals↗
PubMed1991

Role of the GABA chloride ion channel component on aggressive behavior in the male crab.

Picrotoxin blocking effects on GABA-induced inhibition of lateral merus display in the male crab Carcinus mediterraneus suggest that the chloride ion channel component of the GABA molecule is involved in the control of this defensive behavior. The low GABA doses (3 and 5 micrograms/g body weight) inhibited lateral merus display as early as 10 min after drug treatment while the administration of higher GABA concentrations (greater than 5 micrograms/g) prolonged the duration of the behavioral effects. The administration of 1 microgram/g picrotoxin to the animals treated with the effective GABA doses (5, 10 and 20 micrograms/g) restored lateral merus display. The antagonizing activity of picrotoxin on the inhibitory GABA effects, in a temporal manner, demonstrates that GABAergic sites other than peripheral ones are probably participating with the regulation of this agonistic posture. Quantitative autoradiography results revealed interesting receptor levels changes of the specific chloride ion channel antagonist [35S] t-butylbicyclophosphorothionate in the different brain areas of the male crab displaying lateral merus with respect to normal nonreactive animals. Elevated receptor binding levels were encountered in the middle and posterior brain area whereas low levels were obtained at the anterior level. Both the behavioral and autoradiographic results suggest that the defensive type of aggression behavior in crustacean may not only be mediated by a peripherally controlled GABA-gated chloride ion flux but also by a central GABAergic mechanism.

Aggression↗
PubMed1988

Asymptomatic hyperbromidaemia detected as pseudohyperchloridaemia measured with an ion selective electrode meter.

Six patients were found to have increased serum chloride concentrations when these concentrations were determined with an ion-selective electrode, but not when determined by continuous flow mercuric thiocyanate colorimetry or amperometric-coulometric titration. Their serum bromide levels of 1.8-8.0 mmol/l were much higher than those of 0.07-0.13 mmol/l in normal controls. The urinary bromide excretion, measured in two of these patients, was higher than that in normal subjects. No common symptoms or abnormalities in laboratory findings except hyperbromidaemia were found in these patients, who claimed not to have taken any drugs containing bromide. For determination of the incidence of subclinical hyperbromidaemia, the serum bromide concentrations were measured in sera of 1,323 outpatients sent to Tokushima University Hospital for routine measurements of blood chemistry over a one-month period. Five samples showed abnormally high bromide levels. It is concluded that subclinical hyperbromidaemia is not as rare as generally thought, though the aetiology of this state is unknown. Chloride determination with an ion-selective electrode can be used to screen for hyperbromidaemia, since increased levels of bromide ion result in apparently high chloride values.

Adult↗
PubMed1986

Environmentally-related changes in red cell levels of ionic modulators of hemoglobin-O2 affinity in rainbow trout, Salmo gairdneri.

Hemoglobin content, plasma and red cell levels of chloride and magnesium and molar ion:hemoglobin ratios were examined in trout acclimatized to eight combinations of two treatment levels of temperature (5, 20 degrees C), O2 availability (less than or equal to 30%, greater than or equal to 75% saturation) and photoperiod (16L:8D, 8L:16D). Increases in hemoglobin content were associated with exposure to higher temperature, abbreviated daylength and hypoxia, with hypoxia greater than photoperiod greater than temperature. Under nominal "summer" conditions (20 degrees C, hypoxia, 16L:8D) photoperiodic influence was apparently masked by hypoxic and thermal effects. Temperature was the principal determinant of plasma and cellular chloride levels as well as [Cl:Hb]. O2 availability and photoperiod had little effect. Temperature was also the primary factor influencing magnesium, with hypoxia exerting a lesser influence. Photoperiod effects were negligible. With increased temperature and reduced O2 availability, plasma magnesium increased white cell magnesium levels and [Mg:Hb] declined. These observations suggest that with normal seasonal changes in environmental conditions, temperature-induced increases in the O2 requirements of summer trout are probably accompanied by increases in blood O2-carrying capacity and reductions in hemoglobin-O2 affinity with consequent increases in O2 delivery to tissues.

Acclimatization↗
PubMedDate not supplied

Inadequate measurement of urinary chloride.

Urinary electrolytes are invaluable in the differential diagnosis and treatment of certain acid-base diseases. We have evaluated the accuracy and precision of three different automated chemistry analyzers and a chloridometer (Corning 925 Chloridometer, Hitachi 717 and 917 and Vitros 950) for chloride, sodium and potassium using standard solutions. Data indicate that the ISE modules on the Hitachi 717 and 917 analyzers measure sodium and potassium accurately and precisely throughout the studied concentration range. The Vitros 950 system had the poorest precision and accuracy performance at the low levels of sodium and potassium. The chloride ion-selective membranes on the Hitachi analyzers seriously overestimate the chloride concentration at all levels. The manual dilution method on the Vitros 950 analyzer for chloride measurements showed good precision and accuracy only at the higher chloride levels. For chloride determination the chloridometer displayed the best accuracy with good precision. We recommend that laboratories use chloridometers for the measurement of urinary chloride, and that the CAP include low chloride samples in their proficiency testing program for urine chloride.

Autoanalysis↗
PubMed2004

Chloride channel function in the yeast TRK-potassium transporters.

The TRK proteins-Trk1p and Trk2p- are the main agents responsible for "active" accumulation of potassium by the yeast Saccharomyces cerevisiae. In previous studies, inward currents measured through those proteins by whole-cell patch-clamping proved very unresponsive to changes of extracellular potassium concentration, although they did increase with extracellular proton concentration-qualitatively as expected for H(+) coupling to K(+) uptake. These puzzling observations have now been explored in greater detail, with the following major findings: a) the large inward TRK currents are not carried by influx of either K(+) or H(+), but rather by an efflux of chloride ions; b) with normal expression levels for Trk1p and Trk2p in potassium-replete cells, the inward TRK currents are contributed approximately half by Trk1p and half by Trk2p; but c) strain background strongly influences the absolute magnitude of these currents, which are nearly twice as large in W303-derived spheroplasts as in S288c-derived cells (same cell-size and identical recording conditions); d) incorporation of mutations that increase cell size (deletion of the Golgi calcium pump, Pmr1p) or that upregulate the TRK2 promoter, can further substantially increase the TRK currents; e) removal of intracellular chloride (e.g., replacement by sulfate or gluconate) reveals small inward currents that are K(+)-dependent and can be enhanced by K(+) starvation; and f) finally, the latter currents display two saturating kinetic components, with preliminary estimates of K(0.5) at 46 micro M [K(+)](out) and 6.8 m M [K(+)](out), and saturating fluxes of approximately 5 m M/min and approximately 10 m M/min (referred to intracellular water). These numbers are compatible with the normal K(+)-transport properties of Trk1p and Trk2p, respectively.

Biological Transport, Active↗
PubMed2003

Liquid polymer nano-PEBBLEs for Cl- analysis and biological applications.

The first nanometer scale anion sensing fluorescent spherical nanosensors, or PEBBLEs (probes encapsulated by biologically localized embedding) have been developed for the intracellular monitoring of chloride. The general scheme for the polymerization and introduction of sensing components creates a matrix that allows for the utilization of the highly selective ionophores used in poly(vinyl chloride) and poly(decyl methacrylate) ion-selective electrodes. We have demonstrated that our previously developed scheme for cation sensors can be utilized to tailoring selective submicron sensors for use in intracellular measurements of biologically relevant anions for which selective enough fluorescent probes do not exist. Three schemes were attempted for the development of chloride sensitive PEBBLEs. The first two used the Chloride ionophore indium(III) octaethylporphyrin chloride (In(OEP)Cl) (1) as an ionophore working in tandem with a chromoionophore and (2) as a chromoionophore with a peak shift generated by chloride mediated breaking of hydroxide ion-bridged porphyrin dimer. The third method used the optically silent Chloride ionophore III (ETH 9033) working in tandem with chromoionophore III (ETH 5350) to indirectly monitor Cl- activity by reporting the H+ coextracted into the matrix. Method 3 gave the most promising results, at a pH of 7.2 these PEBBLEs have a limit of detection of 0.2 mM Cl- with a linear dynamic range of 0.4 mM-190 mM Cl-. These PEBBLEs were delivered into C6 glioma cells, utilizing a gene gun, and intracellular chloride levels were monitored during ion-channel stimulation by kainic acid.

Animals↗
PubMed2001

Steady-state volumes and metabolism-independent osmotic adaptation in mammalian erythrocytes.

Erythrocytes of various mammalian species -- including human -- maintain osmotic balance with the blood plasma (osmotic activity 270-310 mosmol). However, their intracellular levels of osmotically active ions (potassium, sodium, chloride, and hydrogencarbonate), water content and osmotic resistance deviate significantly. In the present report we study the relationship among intracellular water, potassium and sodium levels of the erythrocytes of various mammalian species and in the developing calf. In addition, the osmotic resistance, K(+) (Rb(+)) uptake and the DPH fluorescence anisotropy of various erythrocytes and erythrocyte ghost membranes were correlated. The results show no statistically significant relationship between erythrocyte water content and [K(+)+Na(+)] levels or K(+)/Na(+) ratios. The reversal of erythrocyte K(+)/Na(+) ratios coincides with the decrease of steady-state ATP levels in the developing calf. The mobility of lipids within the hydrophobic inner layer of the plasma membrane relates closely to passive K(+) (Rb(+)) uptake, and plays a significant role in regulatory volume changes.

Adenosine Triphosphate↗
PubMed1995

Accumulation of glutamate by osmotically stressed Escherichia coli is dependent on pH.

In the present study, we measured the accumulation of glutamate after hyperosmotic shock in Escherichia coli growing in synthetic medium. The accumulation was high in the medium containing sucrose at a pH above 8 and decreased with decreases in the medium pH. The same results were obtained when the hyperosmotic shock was carried out with sodium chloride. The internal level of potassium ions in cells growing at a high pH was higher than that in cells growing in a neutral medium. A mutant deficient in transport systems for potassium ions accumulated glutamate upon hyperosmotic stress at a high pH without a significant increase in the internal level of potassium ions. When the medium osmolarity was moderate at a pH below 8, E. coli accumulated gamma-aminobutyrate and the accumulation of glutamate was low. These data suggest that E. coli uses different osmolytes for hyperosmotic adaptation at different environmental pHs.

Adaptation, Biological↗
PubMed1987

Spontaneous and GABA-evoked chloride channels on pituitary intermediate lobe cells and their internal Ca requirements.

On porcine intermediate lobe (IL) endocrine cells, spontaneously opening chloride channels have been studied and compared to GABA-A activated chloride channels. Elementary currents were recorded mainly from outside-out patches excised from IL cells maintained in culture for 1-4 weeks. Spontaneous inward currents were observed in Cs-loaded cells after replacing Na in the extracellular medium by the impermeant ion choline. This activity, at an internal calcium concentration of 10(-8) M corresponded to a channel for chloride ions with a main conductance level of 26 pS, and substates around 11 pS. The sequence of permeabilities to halides was I greater than Br greater than Cl. These conductance characteristics were common to the GABA-operated channels which also showed a main conductance substate of 23-31 pS. The open time of the 26 pS level mostly encountered in spontaneous activity, was distributed along two modes: one, the most frequent, around 1 ms, and the other around 4 ms. This latter mode was the predominant one observed during GABA and isoguvacine applications but in addition a bursting activity of 19 ms duration was also seen. Specific GABA-A receptor antagonists (bicuculline and SR42641, 1 microM) blocked activity evoked by GABA (1-10 microM), but did not affect spontaneous events. These spontaneous Cl events were only observed in a restricted range of internal Ca concentrations, i.e. between 1 nM and 0.1 microM, and were practically abolished at Cai 1 microM. The GABA-induced activity of Cl channels was also Ca-sensitive, being reduced when Cai reached 1 microM.

Animals↗