Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “Calcium Chloride”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

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

At least 613 records · Page 34Linked to original sources
PubMed1966

Effect of salts and electron transport on the conformation of isolated chloroplasts. I. Light-scattering and volume changes.

Whole chloroplasts isolated from the leaves of spinach (Spinacia oleracea L.) exhibit 2 types of conformational change during electron transport. Amine-uncoupled chloroplasts swell and atebrin-uncoupled chloroplasts shrink. Chloroplasts uncoupled by carbonylcyanide phenylhydrazones and by treatment with ethylenediamine tetraacetic acid do not change their volumes or light-scattering properties during electron transport. Phosphorylating chloroplasts shrink only slightly.The rate and extent of the conformational change parallel the rate of electron transport; both the decrease in turbidity with methylamine and the increase in turbidity with atebrin are rougly proportional to the Hill reaction rate. Consequently the great volume and light-scattering changes which occur in the presence of these uncouplers can be attributed, in part, to the very high rates of uncoupled electron transport. However, for a given rate of electron transport the atebrin-induced scattering increase is very much greater than the increase observed during photophosphorylation.When uncouplers are combined, the carbonylcyanide phenylhydrazone effect (no change) supercedes both the methylamine effect (swelling) and the atebrin effect (shrinking). The methylamine effect supercedes the atebrin (shrinking) and ethylenediamine tetracetic acid (no change) effects. The atebrin effect supercedes the ethylenediamine tetraacetic acid effect. A similar hierarchy of effects is observed with regard to the rate of the uncoupled electron transport.These light-scattering changes of whole chloroplasts reflect similar changes which occur in very small digitonin particles of chloroplasts. Therefore one must look among chloroplast substructures for the basic mechanism of swelling and shrinking.Many salts (including methylamine hydrochloride) cause the chloroplasts to shrink. This phenomenon is not osmotic since comparable osmolarities of sucrose are without effect. Magnesium chloride and calcium chloride are most effective but all salts tested gave major volume decrease when less than 0.05 m. The salt-shrunken chloroplasts show greater light-scattering changes during electron transport than do low-salt chloroplasts.

Journal Article↗
PubMed1980

Kinetic disposition and diuretic effect of frusemide in acute pulmonary oedema.

The kinetic disposition and diuretic effect of frusemide was assessed in 16 patients with acute pulmonary oedema utilizing a specific gas-liquid chromatographic assay for the drug. Serum frusemide concentrations decayed biexponentially with wide variation in both alpha half-life (range 15-79 min) and beta half-life (range 127-1190 min). The beta phase half-life was inversely related to creatine clearance. The apparent volume of distribution varied greatly among the patients (range 0.085-0.818 l/kg), and patients with an acute myocardial infarction had a larger peripheral kinetic compartment. Patients with acute myocardial infarction excreted less unchanged drug and had a lesser urinary excretion of sodium and volume compared to patients without infarction. The urinary excretion of sodium, chloride, calcium and volume was linearly related to the urinary excretion of unchanged frusemide.

Adult↗
PubMed1988

External balance of water and electrolytes in the horse.

The components of the daily external water and electrolyte balances of five normal Standardbred geldings with a mean body weight of 427 kg, were determined over 14 day periods. The mean value of daily total water intake (a summation of free, combined and metabolic water intake) for the group was 27.6 litres, that is, 64.4 ml/kg body weight, while mean values for ambient temperature and humidity ranged from 16 to 25 degrees C and 55.4 to 75.5 per cent, respectively. The mean daily urine volume of 9.9 litres (23.2 ml/kg) for the group, was found to exceed the mean faecal water output of 7.2 litres (16.9 ml/kg). The mean output of sodium for the five animals, in urine and faeces, was 780 mmol or 79 per cent of the intake. The mean output of potassium, chloride, calcium and magnesium were 3163, 2521, 1824 and 1448 mmol or 95, 84, 74 and 75 per cent, respectively of intake. The sodium and potassium not accounted for in urine and faeces may well have been lost in sweat. Results are discussed and compared with those of a previous external balance study in the horse.

Animals↗
PubMed1990

Effect of show jumping on heart rate, blood lactate and other plasma biochemical values.

This study investigated some physiological responses to exercise performed by a horse during show jumping. The effects of jumping on heart rate (HR), blood lactate (LA) and some other blood values were studied in nine normal horses participating at the Belgian Junior Championship. Venous blood was sampled before and immediately after the show jumping and was analysed for packed cell volume, LA, blood glucose (GLU), total plasma protein, bicarbonate, sodium, potassium (K+), chloride, calcium and activities of plasma lactate dehydrogenase, creatine phosphokinase (CK) aspartate amino transferase and gamma glutamyl transferase (GGT). A heart rate recorder placed under the saddle allowed the continuous recording of HR from the warm-up until 2 mins after the event. The completion of the jumping induced significant changes in all values, except in K, GLU and GGT. Resting values of LA and HR were 0.53 +/- 0.05 mmol/litre and 43.9 +/- 1.9 beats/min respectively. Post exercise LA reached a mean value of 9.04 +/- 0.9 mmol/litre, and, during the jumping, HR rose to a peak of 191.4 +/- 3.8 beats/min. The results of this study demonstrate that, although the speed and duration of such an exercise are low, show jumping represents a severe exertion which requires the use of anaerobic metabolism. This implies that the training schedule of jumpers must include power training in order to improve their anaerobic capacity.

Analysis of Variance↗
PubMed1989

On the relation of calcium to ovine parotid secretion.

The effects of Ca2+-active agents on ovine salivary flow rate and composition were measured in parotid glands under several conditions: no stimulation, submaximal stimulation of the secretomotor nerve, or stimulation by the cholinergic agents carbachol or bethanechol. Agents were infused into the arterial blood supply of parotid glands and those investigated were: calcium chloride, the calcium ionophores Bay K8644 and A23187, the calcium chelators EGTA and EDTA, the voltage-dependent calcium channel blocker verapamil and congeners, the calmodulin inhibitor trifluoperazine (TFP) and congeners. None of the agents affected the flow rate of saliva from unstimulated or pharmacologically stimulated glands. Increased plasma [Ca2+] and the ionophores did not affect salivary flow in nerve-stimulated glands. In nerve-stimulated glands, EGTA and TFP reduced salivary flow rate and verapamil increased it. The effect of EGTA was reversed by restoring plasma [Ca2+] to normal (1.0-1.2 mmol/l) or above, but the responses to TFP and verapamil were not reversed by increasing plasma [Ca2+]. In all three conditions of stimulation, infusions of EGTA, verapamil or TFP increased salivary [HPO4(2-)] and reduced [HCO3-] and pH. The ionophores had the opposite effects but increased plasma [Ca2+] had no effect. At the same time, EGTA, verapamil or TFP increased salivary [Na+ + K+], Bay K8644 had the opposite effect but increased plasma [Ca2+] had no effect. The osmolality of the saliva was not altered in any of these circumstances. Salivary [Ca2+] was increased by Ca2+ infusion and reduced by EGTA. Glandular blood flow increased with infusion of agents which increased salivary [HPO4(2-)], fell with infusion of ionophores, and was unchanged by increased plasma [Ca2+]. Thus, there appear to be three calcium-related activities in ovine parotid salivary gland in vivo: (1) salivary flow rate by action at the neuroeffector site, (2) salivary composition by alteration of the ratio of HPO4(2-): HCO3-, and (3) rate of blood flow through the gland by altering vascular resistance.

3-Pyridinecarboxylic acid, 1,4-dihydro-2,6-dimethy↗
PubMed1981

Calcium-Induced Alteration of Cellular Morphology Affecting the Resistance of Lactobacillus acidophilus to Freezing.

Examination of factors affecting the resistance of Lactobacillus acidophilus NCFM culture concentrates to freeze injury induced during frozen storage at -20 degrees C revealed that calcium supplementation of the growth medium contributed to the storage stability of cells prepared in static culture. Culture concentrates of L. acidophilus NCFM were prepared from cells propagated in MRS broth or MRS broth supplemented with 0.1% calcium carbonate, calcium chloride, or calcium phosphate. After 28 days of frozen storage at -20 degrees C, concentrated cells (3.2 x 10 colony-forming units per ml) prepared from MRS broth cultures showed an 84% reduction in viable cells. Of the remaining viable cells, 88% were sublethally injured and unable to form colonies on MRS agar supplemented with 0.15% bile. Cells prepared in calcium-supplemented MRS broths demonstrated more resistance to frozen storage. Viability and injury losses in the frozen concentrates were limited to 10 to 39% and 3 to 23%, respectively. It was observed that calcium supplementation of MRS medium resulted in a morphological transition of L. acidophilus NCFM from filamentous to bacilloid rods, and the bacilloid cells were more resistant to freezing and storage at conventional freezer temperatures. The results suggest that the morphology of the L. acidophilus cell may be an important consideration in the preparation of freeze-stable culture concentrates.

Journal Article↗
PubMed1995

Voltage-gated ion channelopathies: inherited disorders caused by abnormal sodium, chloride, and calcium regulation in skeletal muscle.

The pathological genetic defects in the inherited myotonias and periodic paralyses were recently elucidated using molecular genetic studies. These disorders are usually transmitted as a dominant trait from an affected parent to a child. The many clinical symptoms include cold-induced uncontrollable contraction of muscle, potassium-induced contraction and paralysis, myotonia with dramatic muscular hypertrophy, muscle stiffness, and insulin-induced paralysis (in males). Horses afflicted with the disorder can suddenly collapse, despite an impressive physique. In the past three years, these clinically defined disorders have been shown to share a common etiology: subtle defects of ion channels in the muscle-fiber membrane. Although the specific ion channel involved varies depending on the disease, most patients have single amino acid changes in the channel proteins, with both normal and mutant channels present in each muscle fiber. For each patient, we can now establish a precise molecular diagnosis in the face of overlapping clinical symptoms and begin specific pharmacological treatment based on the primary problem. These studies have also provided insight into basic muscle biology and emphasize the careful regulation of ions in muscle excitation.

Animals↗
PubMed1986

Dependence of ion fluxes on fluid transport by rat proximal tubule.

The effects of changes in transepithelial water flux (Jv) on sodium, chloride, calcium, and potassium transport by the proximal convoluted tubule were examined by applying a microperfusion technique to surface segments in kidneys of anesthetized rats. Perfusion solutions were prepared with ion concentrations similar to those in fluid normally present in the later parts of the proximal tubule. Osmolality of the perfusate was adjusted with mannitol. With no mannitol in the perfusates, net fluid absorption was observed. Addition of increasing amounts of mannitol first reduced Jv to zero and then reversed net fluid flux. At the maximal rates of fluid absorption, net absorption of Na, Cl, Ca, and K was observed. When Jv was reduced to zero, Na, Cl, and Ca absorption were reduced and K entered the lumen. Na, Cl, and Ca secretion occurred in association with the highest rates of net fluid secretion. The lumen-positive transepithelial potential progressively increased as the net fluid flux was reduced to zero and then reversed. The results demonstrate that changes in net water flux can affect Na, Cl, Ca, and K transport by the proximal convoluted tubule of the rat kidney. These changes in net ion fluxes are not entirely accounted for by changes in bulk-phase transepithelial electrochemical gradients.

Animals↗
PubMedDate not supplied

Poisoning due to calcium antagonists. Experience with verapamil, diltiazem and nifedipine.

The calcium antagonists are a heterogeneous class of drugs which block the inward movement of calcium into cells through 'slow channels' from extracellular sites. By inhibiting phase 0 depolarisation in cardiac pacemaker cells and phase 2 plateau in myocardium, and by depressing calcium ion flux in smooth muscle cells of blood vessels, these agents may exert profound effects on the cardiovascular system, particularly in susceptible individuals or in overdose. Sinus node depression, impaired atrioventricular (AV) conduction, depressed myocardial contractility, and peripheral vasodilatation may result. Pharmacokinetic features of calcium antagonists include rapid and complete absorption from the gastrointestinal tract, with extensive first-pass hepatic metabolism yielding generally low bioavailability. The volume of distribution is generally large and protein binding is high. Elimination is almost entirely by the liver. Impaired renal function does not affect pharmacokinetics. Verapamil is the most potent inhibitor of cardiac conduction and contractility, with diltiazem also showing such effects. Nifedipine is the most potent vasodilator, but only occasionally impairs the sinus node or AV conduction. Significant pharmacodynamic effects are common during combination therapy with calcium antagonists, especially verapamil and beta-blockers. Verapamil may significantly elevate serum digoxin concentrations and may exert additive negative effects on chronotropism and dromotropism when this combination is used. Overdoses of calcium entry blockers are becoming more frequent and reflect an extension of the known pharmacodynamic profile of these agents. Typical features include confusion or lethargy, hypotension, sinus node depression and cardiac conduction defects. Onset of symptoms may be delayed if a sustained release preparation is ingested. Management of calcium antagonist overdose includes gut decontamination with lavage and activated charcoal. All symptomatic patients and patients with a history of ingesting a sustained release preparation should be admitted for ECG monitoring. If bradycardia and/or conduction defects contribute to hypotension, atropine or isoprenaline (isoproterenol) may accelerate the ventricular rate. Transvenous pacing may be required. Depressed myocardial contractility usually responds well to calcium chloride or calcium gluconate administration, but further inotropic support may be required. Peripheral vasodilation should be managed with intravenous fluids and a pressor agent such as dopamine or norepinephrine (noradrenaline).

Calcium Channel Blockers↗
PubMedDate not supplied

[Antiarrhythmic properties of the anticonvulsant drug benzonal].

In experiments on albino rats benzonal was found to exert an antiarrhythmic effect on models of chloride calcium-, aconitine- and strophantine-induced arrhythmias. In chloride calcium- and aconitine-induced arrhythmias its effect was qualitatively similar to that of diphenine, however it was inferior by the value of ED50 as compared with the latter. The advantage of benzonal over diphenine was its low toxicity.

Aconitine↗
PubMed1986

Erythrocyte membrane calcium binding in normotensive and hypertensive subjects.

Calcium binding to erythrocyte membranes has been determined in patients with essential hypertension (EHT) and normotensive subjects with (NT + FH) and without (NT - FH) a family history of hypertension, to investigate its relationship to high blood pressure. The calcium content of erythrocyte membranes was measured by atomic absorption spectrophotometry after incubation in 0 (basal) or 40 mmol/l (maximal binding) calcium chloride. Basal calcium binding was reduced to a similar extent in both EHT and NT + FH subjects (11.4 +/- 0.5 and 10.9 +/- 0.9 mumol/g protein versus 13.7 +/- 0.6 mumol/g protein in NT - FH, P less than 0.01 for both). Maximal binding showed a similar pattern. These data suggest that cell membrane calcium binding is not directly related to blood pressure elevation but is the result of an inherited cell membrane defect which is present in essential hypertension patients and their relatives and which affects several membrane functions.

Blood Pressure↗
PubMed1987

Intra-individual variation of some analytes in serum of patients with chronic renal failure.

Biological intra-individual variation in the concentration of 15 biochemical analytes in serum was estimated for 17 patients with chronic renal failure (CRF) and compared with results for apparently healthy individuals. The ratio of the average intra-individual variation in CRF patients to that in normal subjects was 1.5 to 2.0 for sodium, chloride, calcium, and creatinine; 1.2 to 1.5 for hemoglobin, total protein, albumin, globulin, uric acid, cholesterol, and alpha-amylase. The intra-individual CVs for urea, high-density-lipoprotein cholesterol, triglycerides, and alkaline phosphatase did not differ significantly between groups. The intra-individual variation of calcium and the concentration of creatinine in serum correlate significantly (r = 0.661, p less than 0.01). Individual values showed a gaussian distribution for all analytes. There was no time dependence of the intra-individual variation during a three-week interval, except for calcium and cholesterol. The estimated biological component of intra-individual variation and the analytical variation can be used to derive decision-making criteria in monitoring CRF.

Adult↗
PubMed1978

[Anti-arrhythmic activity of trimecaine under experimental and clinical conditions].

The antiarrhythmic properties of trimecaine, a local anesthetic, were studied. Tests on cats and rats with arrhythmia induced by stimulation with electric current and injection of aconitine, barium chloride, and calcium chloride as well as on a cell model of aconitine arrhythmia have shown that trimecaine possesses marked antiarrhythmic properties. It is more active and less toxic than procainamide hydrochloride or quinidine. Oral administration of 0.35% trimecaine solution had a favourable therapeutic effect in extrasystole in patients with complex heart valvular diseases and circulatory disorders. It is presumed that parenteral injection will produce a more rapid and prolonged antiarrhythmic effect.

Acetanilides↗
PubMedDate not supplied

Studies on compensatory adaptation of renal functions.

Changes in the excretion of water and electrolyte in one kidney after exclusion of its partner have been studied in anesthetized dogs and rabbits. Complete clamping of the contralateral kidney pedicle or ureter results in a rapid increase in the excretion of water, sodium, potassium, chloride, calcium, phosphate and bicarbonate. This response is also observed in denervated kidneys. Pretreatment with the loop inhibitor, furosemide, does not preclude adaptation which, however, is blunted by acetazolamide, an inhibitor of proximal sodium and bicarbonate reabsorption. Free-water reabsorption during hypertonic saline diuresis is normal in the remaining kidney. Compensatory adaptation, thus, appears to be located in the proximal tubule. The regulatory response to contralateral kidney exclusion is already fully developed in one-month-old rabbits. Compensatory adaptation of electrolyte excretion is not accounted for by changes in extracellular fluid volume, plasma composition, glomerular filtration rate, effective renal plasma flow, aldosterone or vasopressin.

Acetazolamide↗
PubMed1995

Blood pressure effects of calcium intake in experimental models of hypertension.

Calcium intake has been implicated as being an important factor in the development and treatment of hypertension. The mechanisms underlying the relationship between calcium and blood pressure are not yet clearly defined. Experimental studies have documented an inverse association between calcium intake and blood pressure level. For 15 years it has been shown that calcium supplementation is effective in lowering blood pressure in hypertensive rats and, on the other hand, calcium deprivation results in increased blood pressure levels. Enriched calcium diets decrease blood pressure in genetic hypertension displayed by spontaneously hypertensive rats (SHR), stroke-prone SHR, Lyon hypertensive rats or Dahl salt-sensitive rats and, in volume-dependent hypertension induced by saline and mineralocorticoid or angiotensin II administration in Wistar or Sprague-Dawley rats. Efficacy is observed with calcium carbonate added in the diet and with calcium chloride or calcium gluconate in drinking water. Compared with the normal level in the diet (0.5% to 1%), calcium supplementation represents mainly a fourfold increase whose effect is more intense in young weaning animals treated for a long-lasting period (4 to 10 weeks).

Animals↗
PubMed1981

Total body sodium, calcium, and chloride measured chemically and by neutron activation in guinea pigs.

Body sodium (Na), calcium (Ca), and chloride (Cl) of guinea pigs weighing between 227 and 600 g were measured by total body neutron activation analysis (TBNAA) followed by chemical analysis (CA) on 12-17 animals. Paired t test was used to compare any differences in the results obtained by the two methods. There was no significant difference in the results for the three elements. The means and standard deviation for Ca (g/100 g body wt) 1.070 +/- 0.132 (TBNAA) and 1.107 +/- 0.125 (CA); for Na 0.149 +/- 0.019 (TBNAA) and 0.143 +/- 0.021 (CA); and for Cl 0.126 +/- 0.009 (TBNAA) and 0.132 +/- 0.024 (CA). Neutron activation analysis alone, in a series of 27 animals, gave means (g/100 g body wt) and standard deviation of 1.110 +/- 0.084 for Ca, 0.120 +/- 0.009 for Cl, and 0.153 +/- 0.011 for Na. TBNAA has potential usefulness, particularly in longitudinal studies in the same animal, because of its accuracy and the rapidity and ease with which the measurements can be made.

Animals↗
PubMed2001

Tumor suppression by a proapoptotic calcium-activated chloride channel in mammary epithelium.

Little is known of the roles played by ion channels in cancer. Here we describe a pair of closely related calcium-activated chloride channels whose differential regulation in normal, apoptotic, and transformed mouse cells suggests that channel function is proapoptotic and antineoplastic. While mCLCA1 predominates over mCLCA2 under normal physiological conditions, this relationship is reversed by apoptotic stress both in developing mammary gland and in cultured HC11 mammary epithelial cells. Consistent with an apoptosis-promoting role, splicing of mCLCA2 is disrupted in apoptosis-resistant tumor cell lines and in HC11 cells selected for resistance to detachment-induced apoptosis (anoikis). Unexpectedly, mCLCA1 message is also down-regulated in these cells by at least 30-fold. These results suggest that both genes antagonize survival of mammary tumor cells by sensitizing them to anoikis. When MCF7 or HEK293 tumor cells were transfected with plasmids encoding either mCLCA1 or mCLCA2, colony formation was greatly reduced relative to a vector-transfected control, demonstrating that calcium-sensitive chloride channel (CLCA) expression is deleterious to tumor cell survival. Furthermore, mammary epithelial cells overexpressing mCLCA2 had twice the rate of apoptosis of normal cells when subjected to serum starvation and formed multinuclear giants at a high frequency in normal culture, suggesting that mCLCA2 can promote either apoptosis or senescence.

Amino Acid Sequence↗
PubMed2001

Dietary manipulation to reduce aerial ammonia concentrations in nursery pig facilities.

Two 4-wk trials (preliminary study) and three 5-wk trials (major study) were conducted to determine the effects of adding Yucca schidigera extract or anhydrous calcium chloride to nursery diets on the growth performance of nursery pigs and aerial ammonia concentration. The pigs were weaned between 13 and 15 d of age and had an initial BW of 3 to 6 kg. In each trial, pigs were allotted to three identical pig nursery rooms that were environmentally regulated. There were three diets (one diet per room): 1) control, containing 23% CP; 2) control plus 125 ppm of Yucca schidigera extract; and 3) control plus 1.95% anhydrous calcium chloride. Growth performance was recorded weekly. Aerial ammonia concentration was measured daily using aspiration detector tubes and during the last week of each trial using diffusion tubes. Manure samples were collected twice a week during the experimental period to determine ammonia and N concentrations and pH. Plasma urea concentration was determined in blood samples collected from the pigs at the end of each trial. Data were analyzed using split-plot and Latin square designs for the preliminary and major studies, respectively. Feed intake was similar among pigs fed all three diets. There were no differences in ADG and ADG/ADFI (G/F) between pigs fed the control diet and pigs fed the yucca extract diet (P > or = 0.41). In all trials, pigs fed the calcium chloride diet had lower ADG and G/F than pigs fed the other two diets (P < 0.05). In the preliminary study, aerial ammonia tended to be greater in the rooms in which pigs were fed the control diet than in the rooms with pigs fed the yucca extract diet (P = 0.08) and the calcium chloride diet (P = 0.11). In the major study, aerial ammonia increased weekly (diet x week; P < 0.001) in all rooms. In the 4th wk, ammonia concentrations were greater (P < 0.001) in the rooms in which pigs were fed the control diet than in the rooms in which the other two diets were fed. Dietary treatment had no effect on plasma urea concentration (P > or = 0.10), manure ammonia and N concentrations (P > or = 0.50), and manure pH (P > or = 0.78). Although aerial ammonia concentrations were relatively low, the addition of Yucca schidigera extract or calcium chloride to the diet of nursery pigs reduced ammonia concentrations in the nursery rooms.

Air Pollutants↗