Na2EDTA Infusion Research Articles

Effects of Ammonium Chloride and Sulfate on Acid-Base Status and Calcium Metabolism of Dry Jersey Cows

Eight nonlactating, nonpregnant Jersey cows were used in a crossover experiment with two 28-d periods. The control diet consisted of corn silage plus a concentrate mix (68:32, DM basis). The treatment diet was the same, except that and NH4Cl (NH3)2SO4 (98g of each/d per cow) were added to the concentrate. Cows fed the treatment diet had lower blood pH, higher ionized Ca in blood, and more urinary excretion of Ca, titratable acid, and ammonium than cows fed the control diet. For cows fed the treatment diet, ionized Ca in blood was greater after equal amounts of Na2-EDTA were infused to both treatment groups, and treatment cows recovered faster after infusion of Na2-EDTA was stopped than did control cows. The treatment diet induced mild metabolic acidosis and increased the cows’ ability to maintain normal blood Ca concentrations; it potentially could reduce incidence of milk fever.

Effects of Diets Magnesium on Acid-Base Status and Calcium Metabolism of Dry Cows Fed Acidogenic Salts

The objective was to study effects of dietary Mg on acid-base status and Ca metabolism of Holstein cows fed acidogenic diets with relatively high Ca concentrations. Eight nonlactating, nonpregnant Holstein cows were used in a switchback experiment with three 28-d periods. The normal Mg (.2%, dry basis) diet consisted of corn silage plus a concentrate mix supplemented with NH4Cl (126 g/d per cow) and (NH4)2SO4 (126 g/d per cow). The high Mg (.37%, dry basis) diet had MgSO4 substituted for an equivalent amount of s supplied by (NH4)2SO4 in the normal Mg diet. Cation-anion differences of the two diets were –302 (normal Mg) and –289 (high Mg) meq/kg of dietary DM. Compared with cows fed the normal Mg diet, those fed high Mg tended to have higher blood pH and plasma concentrations of total Ca but lower plasma concentrations of P and lower urinary excretion of ammonium and net acid. Cows fed the high Mg diet also tended to increase in urinary excretion with a decrease in urinary excretion of Ca. Metabolic responses to intravenous infusion of Na2-EDTA were similar among cows fed either diet. Results indicate that increasing salts was of no advantage with regard to Ca metabolism.

Arteriographic findings in EDTA chelation therapy on peripheral arteriosclerosis

In a randomized, double-blind, controlled study, 153 patients with claudication were each given either 20 infusions of Na 2EDTA or 20 infusions of saline. Walking distances and ankle/brachial indices were measured before, during, and after treatment. In 30 patients, angiograms and transcutaneous oxygen tensions were obtained before, during, and after treatment. The patients' subjective evaluations of the effect of treatment were also recorded. It is concluded that EDTA chelation therapy has no effect in patients with intermittent claudication in the legs caused by arteriosclerosis.

Radioimmunoassay of parathyroid hormone in cats

SUMMARY A radioimmunoassay for measurement of midmolecule parathyroid hormone (pth) concentration in serum from dogs was validated for use on serum from cats. The assay detected an increase in serum concentration of pth after iv infusion of Na2 edta in healthy cats. Infusion of calcium chloride caused a decrease in measured pth. Accuracy of the assay was demonstrated by quantitative recovery of a feline parathyroid gland extract added to pooled feline sera. Mean interassay and intra-assay coefficients of variation were 0.13 and 0.07, respectively. Sensitivity of the assay was 0.1 ng of pth/ml. The median pth concentration measured in 40 adult cats was 3.5 ng/ml, with a range of 1.16 to 11.0 ng/ml.

A Comparison Between the Main Clinical Signs of Milk Fever in Cows with Those of Hypocalcaemia Induced by Na2EDTA Solution

In one study, 6 cows with high erythrocyte potassium concentrations (HK cows) and 7 with low erythrocyte potassium concentrations (LK cows) were infused with 4.7% Na2EDTA solution intravenously for 4 h. The immediately observable clinical signs and the sequelae over a period of weeks were recorded and compared. There were no differences in the clinical responses of HK or LK cows to the infusion of Na2EDTA. In a second study, these clinical signs plus those produced experimentally by three other research groups were compared with both the clinical signs of milk fever recorded in three text books and those observed by one of the authors over a period of 25 years in dairy cattle practice. All of the clinical signs of milk fever occurred in the experimental model, but there were extra signs (excessive salivation, excessive lip and tongue actions, and tail lifting) which were not present or recorded in naturally occurring cases of hypocalcaemia. Hypocalcaemia induced in cows by the intravenous infusion of 4.7% Na2EDTA solution is a reasonably good model for the reproduction of the clinical signs of milk fever, but because of the extraneous signs, and the unusual nature of the subsequent deaths of 3 of 13 cows infused for 4 h, and the death of 1 of 2 cows infused for 4 h daily for 3 days, the model may not be a valid one for periods longer than 4 h in cows.

Clinical performance of a parathyrin immunoassay with dynamically determined reference values.

We compared the clinical performance of a carboxyl-terminal radioimmunoassay for human parathyroid hormone (iPTH), using either a dynamic reference interval (95% confidence limits of serum iPTH concentrations observed in 11 normal individuals during intravenous infusions of Na2EDTA and CaCl2) or a gaussian (2 SD) reference interval derived from 233 normocalcemic individuals. The 2 SD ranges were 3.5 to 9.8 pmol/L for serum iPTH and 2.19 to 2.53 mmol/L for total calcium. The iPTH dynamic interval was lower for calcium concentrations greater than 2.50 mmol/L; it was higher, wider, and continued to increase for calcium values less than or equal to 2.25 mmol/L. Use of the dynamic reference interval increased the clinical sensitivity of our assay from 81% and 61% to 100%, respectively, in primary hyperparathyroidism (n = 47) and hypoparathyroidism (n = 18). Test specificity was maintained at 100% in hypocalcemic disorders but fell to 93% (62/67) in hypercalcemic disorders. Overall, use of the dynamic reference interval improved the assay performance.

Improved differential diagnosis of hypercalcemia by hypocalcemic stimulation of parathyroid hormone secretion.

AbstractIn vitro experiments have indicated that in primary hyperparathyroidism (HPT) the hyperfunctioning glands have a set point error, i.e., they are not autonomous but regulate serum calcium around a hypercalcémie value. In contrast, parathyroid function is suppressed in patients with hypercalcemia of causes other than HPT (e.g., malignancy or sarcoidosis). The basal measurements of serum parathyroid hormone (PTH) levels, however, cannot, alone, separate with precision HPT from other causes of hypercalcemia.Lowering of calcium, in order to stimulate secretion of PTH, was, therefore, achieved by either infusion of Na2 EDTA (24 mg/kg per hr) for 1 hour, or intramuscular injection of 100 IU salmon calcitonin.All 35 patients with primary HPT displayed a significant increase of serum PTH concentrations, evaluated by a midregion/intact hormone assay, during the EDTA infusion, which lowered plasma ionized calcium by an average of 0.16 mmol/l. The injection with calcitonin reduced the calcium concentrations by 0.10 mmol/l after 8 hours and caused a rise in PTH in 80% of HPT patients. With both tests, the secretory response by PTH to the reduction of plasma calcium was generally evident while the patients were still hypercalcemic.In 32 patients with other causes for hypercalcemia, primarily malignancy and sarcoidosis, similar reductions of plasma ionized calcium were obtained. In contrast to the HPT patients, none of them raised their serum PTH values during the test. Thus, stimulation of PTH secretion by a moderate reduction of serum calcium considerably improves the differential diagnosis of hypercalcemia since a significant secretory response appears to be exclusive for HPT.

Induced hypocalcaemia in ruminants: Changes in some parameters of circulatory function

Hypocalcaemia was induced in cows and sheep by Na 2EDTA infusion and the plasma calcium concentrations then related to cardiac output, stroke volume, mean right atrial pressure, mean right ventricular pressure, mean pulmonary arterial pressure, right ventricular work against pulmonary arterial pressure and pulmonary vascular resistance. It was found that for a fall in plasma calcium concentration of 1 mmol/l in cows cardiac output was reduced by 38 ml/kg bwt/min, stroke volume by 0·64 ml/kg bwt/beat, mean right atrial pressure increased by 7·6 mmHg, mean right ventricular pressure increased by 5·9 mmHg, mean pulmonary arterial pressure increased by 6·8 mmHg, right ventricular work against pulmonary arterial pressure decreased by 28·1 J/min and pulmonary vascular resistance increased by 41 dyn·cm 5/s. In sheep cardiac output was reduced by 37·3 ml/kg bwt and stroke volume by 0·48 ml/kg bwt/beat for a fall in plasma calcium concentration of 1 mmol/1. The significance of these findings in hypocalcaemic disorders is discussed.

Influence of prepartum calcium intake on calcium mobilization rate around parturition in dairy cows fed at a high prepartum feeding level.

The influence of a low and a high prepartum calcium (Ca) intake on Ca mobilization rate around parturition was studied in 44 dairy cows fed a ration sufficient for 1.90 times maintenance requirements during the dry period. The plasma Ca level declined on the day of parturition in the group fed the low Ca intake (LCa: 26.4 g/d) as well as in the group fed the high Ca intake (HCa: 87.2 g/d). Plasma Ca levels of the HCa group were lower at parturition, and in this group 1 cow had milk fever after parturition. In the HCa group 6 cows had a plasma Ca level less than or equal to 2.0 mmol/l at parturition and/or 10 h post-partum (pp), versus 1 cow in the LCa group. Na2EDTA was intravenously infused at 10 h pp to induce hypocalcaemia to a level of plasma Ca not bound to EDTA of approximately 1.0 mmol/l. The LCa groups tended to require more Na2EDTA than the HCa groups, however the difference was significant only in the younger cows. After the Na2EDTA infusion 7 cows of the HCa group and 1 of the LCa group did not recover spontaneously and needed to be treated. The mean plasma PTH levels of the LCa group ante-partum were slightly higher than those of the HCa group. The Ca level of the prepartum ration did not influence urinary hydroxyproline excretion, which suggests that the Ca intake of 26.4 g/d was too high to stimulate bone turnover. Comparison of the present results with those of an earlier experiment in which the prepartum Ca intake at a low feeding level (1.12 times maintenance) was studied, led to the conclusion that higher prepartum feed intake has a clear negative influence on Ca homeostasis around parturition.

Effects of low and high calcium intake prepartum on calcium mobilization rate around parturition in dairy cows.

Forty-one dairy cows were fed a low (LCa-13 g/d) and a high (HCa-83.5 g/d) calcium ration in the 8 weeks prior to parturition and the effect on the Ca mobilization rate around parturition was studied. Plasma Ca values were stable in the LCa group around parturition. In the older cows of the HCa group a very slight decrease in the mean plasma Ca was observed: 2.58 mmol/l at 12-36 h ante partum decreased to 2.38 mmol/l at parturition. Hypocalcaemia, which commonly occurs around parturition, did not occur in 40 of the cows. A subclinical hypocalcaemia (1.8 mmol/l) occurred in one cow (parity 10) from the HCa group. To assess the efficiency of Ca mobilization, a severe hypocalcaemia (1.0 mmol/l) with clinical signs was induced by means of Na2EDTA infusion (0.90 mmol/min), starting at 10 h post-partum. The older cows in the LCa group required more Na2EDTA than those in the HCa group. Higher urinary hydroxyproline excretion in the week before parturition in the LCa than in the HCa group suggested a higher bone turnover. Plasma PTH levels around parturition were not significantly different between the groups. The amount of colostrum milked out in the first 10 h post-partum did not influence Ca homeostasis around parturition. The results contradict those of many other experiments in which hypocalcaemia was observed in cows ingesting high levels of Ca. It is concluded that the restricted feed intake prepartum possibly had a favourable effect on Ca homeostasis.

The effect of experimentally induced hypocalcaemia on uterine activity at parturition in the ewe

The effect of hypocalcaemia experimentally induced by the intravenous infusion of ethylene-diamine tetraacetic acid, disodium salt (Na 2EDTA) upon myometrial activity at parturition was studied in eleven ewes. Infusions of Na 2EDTA were performed during first stage of labour (three animals), second stage (four animals), third stage (three animals) and postpartum (two animals); one in the latter group had been previously treated during second and third stages. Uterine activity was recorded using balloon-tipped catheters surgically implanted into the uterus and was expressed in Montevideo Units (M.U.). Plasma calcium (nonchelated) concentrations were monitored throughout the infusion. Induced hypocalcaemia resulted in a reduction of the activity of the uterus when Na 2EDTA was administered during the first stage of labour. In the ewes infused during the second stage of labour, there was difficulty in reducing the activity of the uterus and, consequently, in delaying parturition. Reduction in uterine activity was easier in the ewes infused during the third stage of labour and during postpartum. Uterine activity started decreasing when plasma calcium concentrations were 6.6 and 7.1 mg/100 ml in the ewes infused during third stage of labour and postpartum, respectively, compared with 4.9 mg/100 ml in those infused during first stage of labour; the difference between this last group and the first two was significant (p < 0.05). After the end of the infusion, the plasma calcium started rising and normal uterine activity quickly resumed.

The effect of calcium ions chelation and sodium ions excess in the cerebrospinal fluid on body temperature in conscious dogs.

The effects of chelation of calcium ions and elevation of sodium ions concentration in cerebrospinal fluid on body temperature was examined in conscious dogs. Decrease of calcium ions concentration brought about by an infusion of disodium edetate (Na2EDTA) into the lateral ventricle elicited an increase in body temperature in 8 out of 10 experiments by 1.49±0.36°C. Huddling, piloerection, lowering of respiratory rate, vasoconstriction and shivering occurring in the course and after Na2EDTA infusion argue that hyperthermia resulted both from excess production of heat and activation of heat conservation mechanisms. Two intraventricular infusions of artificial CSF containing 88 mM Na+ in excess of its physiological concentration did not produce any effect on body temperature.

The effect of chelation of calcium ions in cerebrospinal fluid on the osmotic thirst in dogs.

The osmotic reactivity of the thirst mechanism was examined in conscious dogs implanted chronically with cannulas in the lateral ventricle and with thermistors in the anterior hypothalamus. The experiments were performed under control conditions and after chelation of calcium ions of the cerebrospinal fluid by infusion of sodium edetate (Na2 EDTA) into the ventricle.In seven out of nine experiments infusion of Na2 EDTA caused an increase in deep body temperature of 1.70 «; 0.35°C and marked elevation of the thirst threshold to the osmotic stimulus. The threshold cellular dehydration causing drinking increased from 2.54 ± 0.63% of intracellular water (ICW) to 6.80 ± 1.57 of ICW. In two experiments, in which infusion of Na2 EDTA did not increase deep body temperature, water intake was enhanced.The possible mechanism of these effects is discussed.

Parathyroid effects on renal phosphorus excretion in the cow.

ARTICLESParathyroid effects on renal phosphorus excretion in the cowGP Mayer, RR Marshak, and DS KronfeldGP MayerSearch for more papers by this author, RR MarshakSearch for more papers by this author, and DS KronfeldSearch for more papers by this authorPublished Online:01 Dec 1966https://doi.org/10.1152/ajplegacy.1966.211.6.1366MoreSectionsPDF (1 MB)Download PDF ToolsExport citationAdd to favoritesGet permissionsTrack citations ShareShare onFacebookTwitterLinkedInWeChat Previous Back to Top Next Download PDF FiguresReferencesRelatedInformation Cited ByThe potential for pharmacological supply of 25-hydroxyvitamin D to increase phosphorus utilisation in cattleAnimal Production Science, Vol. 53, No. 11Phosphorus Partitioning During Early Lactation in Dairy Cows Fed Diets Varying in Phosphorus ContentJournal of Dairy Science, Vol. 85, No. 5Effect of dietary calcium and phosphorus vitamin D metabolites 25(OH)D and 1,25(OH)2D, and response to bPTH (1-34) in blue duikers26 April 2002 | Zoo Biology, Vol. 21, No. 2Experimental Hypocalcemia Induced by Hemodialysis in Goats.Journal of Veterinary Medical Science, Vol. 61, No. 12Renal Phosphate Excretion in GoatsJournal of Veterinary Medicine Series A, Vol. 45, No. 1-10Serum concentrations of total and ionized calcium and magnesium and inorganic phosphate during Na2EDTA infusion in dairy cows20 January 2011 | Journal of Animal Physiology and Animal Nutrition, Vol. 77, No. 1-5Calcium Metabolism in Hypocalcemic Cows with Myocardial Lesion.Journal of Veterinary Medical Science, Vol. 59, No. 11α-Hydroxyvitamin D3 Plus 25-Hydroxyvitamin D3 Reduces Parturient Paresis in Dairy Cows Fed High Dietary CalciumJournal of Dairy Science, Vol. 75, No. 2Changes in Concentrations of Certain Plasma and Erythrocyte Minerals Associated with Hypomagnesaemia in Young CalvesJournal of Veterinary Medicine Series A, Vol. 36, No. 1-10Influence of Magnesium, Water, and Sodium Chloride on Urolithiasis in Veal CalvesJournal of Dairy Science, Vol. 71, No. 12Induced hypocalcaemia in ruminants: Changes in some parameters of circulatory functionBritish Veterinary Journal, Vol. 144, No. 3Effect of Synthetic Bovine Parathyroid Hormone in Dairy Cows: Prevention of Hypocalcemic Parturient ParesisJournal of Dairy Science, Vol. 69, No. 9Renal Percent Clearance Ratios in CattleVeterinary Clinical Pathology, Vol. 14, No. 1Vitamin D Metabolism in Ruminants and Its Relevance to the Periparturient CowJournal of Dairy Science, Vol. 66, No. 4Calcium and phosphate homoeostasis in ruminants and its relationship to the aetiology and prevention of parturient paresisPhosphorus in rangeland ruminant nutrition: A reviewLivestock Production Science, Vol. 7, No. 1Species differences in the effect of parathyroid hormone on cyclic amp productionComparative Biochemistry and Physiology Part A: Physiology, Vol. 67, No. 3Induced Hypocalcaemia in Cows and Sheep. I. Changes in Plasma Inorganic Phosphorus LevelsBritish Veterinary Journal, Vol. 135, No. 5Parturient Hypocalcemia, Hypomagnesemia, Mastitis–Metritis–Agalactia Complex of SwineBIBLIOGRAPHYThe Effect of Thyroidectomy and Thyroparathyroidectomy upon Phosphorus Homeostasis in the Goat: a Hypothesis for the Cause of HypophosphataemiaResearch in Veterinary Science, Vol. 11, No. 3The Effect of Thyroparathyroidcctomy upon Phosphorus Homeostasis in the Adult GoatResearch in Veterinary Science, Vol. 10, No. 6Parathyroid Influences upon Phosphorus Balance and Homeostasis in Cows ,The Journal of Nutrition, Vol. 95, No. 2 More from this issue > Volume 211Issue 6December 1966Pages 1366-1370 Copyright & PermissionsCopyright © 1966 by American Physiological Societyhttps://doi.org/10.1152/ajplegacy.1966.211.6.1366PubMed5956551History Published online 1 December 1966 Published in print 1 December 1966 Metrics

Treatment of cardiac arrhythmias with salts of ethylenediamine tetraacetic acid (EDTA)

1. 1. An average of 2.8 (0.5 to 4.0) Gm. of Na 2EDTA was given intravenously to 46 patients with cardiac arrhythmias. The side effects were minor. The concentration of serum calcium decreased on an average of 1.18 mEq./L. Atrial ectopic beats were abolished or significantly suppressed in 7 out of 14 patients, and ventricular ectopic beats were suppressed in 16 out of 25 patients. In 9 instances of atrial fibrillation and 4 of atrial flutter, Na 2EDTA was ineffective. Atrial flutter was abolished in one patient. 2. 2. Na 2EDTA was about equally effective in suppressing ectopic beats in patients not receiving digitalis as in those receiving it. There was no difference in the effect of Na 2EDTA in patients without heart disease and in those with varying degrees of heart disease. The success or failure was not related to changes in heart rate or degree of induced hypocalcemia. 3. 3. The suppression of ectopic beats after infusion of Na 2EDTA was attributed to the induced hypocalcemia, because in the majority of patients in whom calcium chloride was given after termination of the infusion of Na 2EDTA, the ectopic beats reappeared. 4. 4. The main effect of induced hypocalcemia on the electrocardiogram consisted of prolongation of the S-T segment and of the coupling interval of the premature beats. The latter was attributed to lengthening of the refractory phase of the ventricular myocardium, which was considered as a possible mechanism of the action of Na 2EDTA on ectopic beats. 5. 5. Intravenous infusion of KCl followed infusion of Na 2EDTA in 10 patients. In addition, 11 patients received an intravenous infusion of 1.3 to 3.0 Gm. of K 2EDTA. The combined administration of chelating agent and potassium appeared to have a stronger antiarrhythmic action than did the infusion of either substance alone in only a very few cases.