Effect of Magnesium Deficiency and Excess on Renal Tubular Potassium Transport in the Rat

1981 ◽  
Vol 60 (5) ◽  
pp. 549-554 ◽  
Author(s):  
S. L. Carney ◽  
N. L. M. Wong ◽  
J. H. Dirks
Keyword(s):  
Magnesium Deficiency ◽  
Distal Tubule ◽  
Fractional Excretion ◽  
The Body ◽  
Control Group ◽  
Potassium Excretion ◽  
Potassium Homeostasis ◽  
Dietary Magnesium ◽  
Magnesium Status ◽  
Total Body

1. Dietary magnesium deficiency is commonly associated with significant potassium depletion although the mechanisms responsible are unknown. Because the kidney has an important role in both magnesium and potassium homeostasis, clearance and micropuncture experiments were performed on thyroparathyroidectomized magnesium-deficient, normal and hypermagnesaemic rats to study the effect of body magnesium status on renal potassium handling. 2. Dietary magnesium restriction that reduced total-body magnesium by 30% did not alter renal potassium excretion despite a 10% reduction in total-body potassium. Graded magnesium infusions increased the fractional excretion of potassium in both magnesium-depleted and normal rats. However, the increase in the dietary depleted group was significantly less than in the control group (5-10 and then 13% compared with 7-19 and then 28% respectively). These changes in urine potassium excretion followed alterations in distal-tubule function. Parathyroid hormone did not alter potassium excretion in any of the experimental groups in contrast with its effect on magnesium excretion. 3. These data support the concept of distal tubular control of renal potassium homeostasis. The body magnesium status appears to exert some control over cellular potassium content and to alter indirectly distal-tubule potassium excretion.

scholarly journals Magnesium: Biochemistry, Nutrition, Detection, and Social Impact of Diseases Linked to Its Deficiency

Nutrients ◽  
2021 ◽  
Vol 13 (4) ◽  
pp. 1136
Author(s):  
Diana Fiorentini ◽  
Concettina Cappadone ◽  
Giovanna Farruggia ◽  
Cecilia Prata
Keyword(s):  
Social Impact ◽  
Magnesium Deficiency ◽  
Serum Magnesium ◽  
Serum Levels ◽  
Point Of View ◽  
Magnesium Concentration ◽  
Multiple Perspectives ◽  
Dietary Reference Values ◽  
Magnesium Status ◽  
Total Body

Magnesium plays an important role in many physiological functions. Habitually low intakes of magnesium and in general the deficiency of this micronutrient induce changes in biochemical pathways that can increase the risk of illness and, in particular, chronic degenerative diseases. The assessment of magnesium status is consequently of great importance, however, its evaluation is difficult. The measurement of serum magnesium concentration is the most commonly used and readily available method for assessing magnesium status, even if serum levels have no reliable correlation with total body magnesium levels or concentrations in specific tissues. Therefore, this review offers an overview of recent insights into magnesium from multiple perspectives. Starting from a biochemical point of view, it aims at highlighting the risk due to insufficient uptake (frequently due to the low content of magnesium in the modern western diet), at suggesting strategies to reach the recommended dietary reference values, and at focusing on the importance of detecting physiological or pathological levels of magnesium in various body districts, in order to counteract the social impact of diseases linked to magnesium deficiency.

scholarly journals Challenges in the Diagnosis of Magnesium Status

Nutrients ◽  
2018 ◽  
Vol 10 (9) ◽  
pp. 1202 ◽  
Author(s):  
Jayme Workinger ◽  
Robert. Doyle ◽  
Jonathan Bortz
Keyword(s):  
Mineral Content ◽  
Magnesium Deficiency ◽  
The Body ◽  
Dietary Practices ◽  
Disease States ◽  
Metabolic Functions ◽  
Magnesium Status ◽  
Critical Mineral ◽  
Unique Mechanism

Magnesium is a critical mineral in the human body and is involved in ~80% of known metabolic functions. It is currently estimated that 60% of adults do not achieve the average dietary intake (ADI) and 45% of Americans are magnesium deficient, a condition associated with disease states like hypertension, diabetes, and neurological disorders, to name a few. Magnesium deficiency can be attributed to common dietary practices, medications, and farming techniques, along with estimates that the mineral content of vegetables has declined by as much as 80–90% in the last 100 years. However, despite this mineral’s importance, it is poorly understood from several standpoints, not the least of which is its unique mechanism of absorption and sensitive compartmental handling in the body, making the determination of magnesium status difficult. The reliance on several popular sample assays has contributed to a great deal of confusion in the literature. This review will discuss causes of magnesium deficiency, absorption, handling, and compartmentalization in the body, highlighting the challenges this creates in determining magnesium status in both clinical and research settings.

scholarly journals Advantage of Early Tangential Necrectomy in Extensive Pediatric Burns

2019 ◽  
Vol 3 (2) ◽  
Author(s):  
Kenan Karavdić
Keyword(s):  
Body Weight ◽  
Hospital Stay ◽  
Body Surface ◽  
The Body ◽  
Morbidity And Mortality ◽  
Control Group ◽  
Clinical Parameters ◽  
Laboratory Values ◽  
Pediatric Burns ◽  
Total Body

Background: An extensive burn is one of the most serious injuries. The modern treatment of pediatric burns is a logical exercise in resuscitation, infection control, surgical wound care, nutrition and psychologic and physical rehabilitation. The conventional methods of local therapy, especially in extensive and deep burns, cannot prevent infection. The fact is that the necrotic burn tissue always gives rise to infection and must therefore be excised. Tangential excision is a diagnostic procedure as well as a surgical preparation of a recipient bed for skin graft.  Clinical parameters of sixty extensively burned children have been evaluated, divided into two groups (surgically and non-surgically treated) and in four subgroups (under and over the 25% TBSA). The following criteria have been used to compare the results: pain, fever, body weight, duration of the hospital stay, wound infenction, laboratory values. Aim of research: The aim of our research was to demonstrate the efficacy of early tangential necrectomy in the treatment of extensive burns in children as well as in preventing the burn diseases. Material and methods: Clinical parameters of sixty extensively burned children have been evaluated, divided into two groups (surgically and non-surgically treated) and in four subgroups (under and over the 25% TBSA). The following criteria have been used to compare the results: pain, fever, body weight, duration of the hospital stay, wound infection, laboratory values. Results: The boys comprised 58.3% of the respondents and the girls were 41,7% of the respondents. The most common cause was the hot liquid of 73.3%, open flame 23.3% and the contact with hot metal 3.3%. The body temperature was significantly higher in control group compared to the examined group (p <0.001) significantly lower hematocrit values in the control group compared to the examined group (p = 0.002).      The results show that hospitalization lasted considerably longer in patients in the control group than in the examined group (p = 0.003). The incidence of bacterial infection of the burns is significantly higher in control compared to the examined group of patients (p = 0.007). The most commonly isolated bacteria in the study group was Staphylococcus aureus (15/30 or 50% of all subjects). Acinetobacter spp. was isolated in 9 patients (30% of respondents). Serratia spp. And Enterococcus Foecalis were isolated in 6 patients (20%). Pseudomonas aeruginosa was isolated in 3 patients (10%). Three patients (10%) did not isolate any bacteria during hospitalization Conclusions: The method of early tangential necrectomy of extensively burned children significantly reduce morbidity and mortality (it improves the general condition of the patient, improves clinical and laboratory parameters, reduces the possibility of infection of the wound, reduces the possibility of sepsis, reduces the length of hospitalization).The most optimal time to perform an early tangential necrectomy is the period between the 4th and the 6th day after the injury. In extensively burned children over 30% of the total body surface, an early tangential necrectomy should be performed on an area of about 20% of the total body surface as a prevention of blood loss due to necrectomy and autotransplantation. With extensively burned children over 40% of the total body surface, taking homotransplants from parents or close relatives reduces morbidity and mortality.

scholarly journals Internal Proportions of The Body Composition in Members of the Female National Tennis Team of Poland

2018 ◽  
Vol 2 (73) ◽  
Author(s):  
Marina Jagiello ◽  
Wladislaw Jagiello
Keyword(s):  
Body Composition ◽  
Body Size ◽  
Body Mass ◽  
Body Height ◽  
The Body ◽  
Control Group ◽  
Tennis Players ◽  
National Team ◽  
The Mean ◽  
Total Body

Contemporary anthropological research confirms the fact that body composition is one of the basic elements differentiating athletes from persons not practising sport. Among athletes representing various branches of sport there are also significant differences in their body composition. Internal proportions of the body composition of an athlete, or a selected group of athletes, is an especially important yet little researched issue of sports anthropology. This problem is still topical in sports games, especially in tennis. Therefore, the aim of the study was to determine internal proportions of the body composition of female tennis players from the Polish national team in comparison to persons who do not practice sport professionally. The study involved female athletes of the Polish national tennis team (n = 10). The study was carried out in a training camp from 28 September to 9 October 2002 in Zakopane — Centre of Sports Preparation. Athletes’ age was 16—20 (18.1 ± 1.4) years, and the training experience 8—12 years (10.5 ± 1.8). The mean body height for the group members was 171.9 ± 6.7 cm and the mean body mass 59.7 ± 6.3 kg. The results of research by Piechaczek et al. (1996) constituted the reference point for the results of measurements of Polish tennis representatives. The authors studied 153 female students of Warsaw Technical University aged 20.2 ± 1.09 years. They were randomly chosen students of the first and the second year of various departments at this university. The mean body height of the students was 166.2 ± 6.2 cm and the mean body mass 57.4 ± 7.72 kg. Anthropometric measurements were taken using standard instruments (Drozdowski, 1998). The analysis involved 11 somatic features which determined three so-called factors of body composition: length (m1), stoutness (m2) and obesity (m3). The assessment of proportions of the body composition was made by means of Perkal’s natural indices (1953) with Milicerowa’s modifications (1956). We determined the following: composition factors (m), index of total body size (M), internal proportions of the body composition, evenness of composition, the code of internal proportions; also the assessment of internal proportions of the body composition within each of the factors.Taking into consideration the mean values of the studied somatic features in the control group and the comparative group we found differences in their body composition. The representatives of the Polish national tennis team showed substantially longer upper and lower limbs, and the body height was greater. They also had much greater forearm perimeter and shorter pelvic width. As to the total body size, the tennis players slightly exceeded the students (M = 0.24). The total body size (M) resulted from high values of length features (m1 = 1.01), low ones of stoutness (m2 = –0.39) and medium ones of obesity (m3 = 0.1). The value of the intragroup variability index (harmony of composition) amounted to 1.4 and the code of internal proportions of tennis players’ body composition — to 6—2—4. The proportions of internal features of the stoutness index (natural indices of features within a factor) showed the advantage of the forearm perimeter (1.62) and elbow width (0.36). The knee width (–1.30) and pelvic width (–0.60) were disproportionate to the total value of this factor. The input of features characterizing the length factor was relatively proportional.Keywords: tennis, training, body composition, internal proportions.

Measurements of Alterations in Bone Mineral Density, and Body Composition in a Group of Type-2 Diabetic Women

2021 ◽  
Vol 19 (7) ◽  
pp. 48-56
Author(s):  
Khalid Ghanim Majeed ◽  
Muthanna Hashim Dawood ◽  
Ali Khairaldeen Mohialdeen
Keyword(s):  
Body Composition ◽  
Lumbar Spine ◽  
Fat Mass ◽  
Total Body Water ◽  
The Body ◽  
Healthy Control Group ◽  
Control Group ◽  
Healthy Control ◽  
Total Body

Aim: To assess the body composition of fat mass, lean mass, visceral fat mass, and total body water in DM patients and compares their findings with a healthy control group. Material and Methods: A total of 86 people including 40 diabetes Mellitus type 2 matched for sex and age with 46 healthy control participated in the study. BMDs of the lumbar vertebrae and the hip regions like (total femur, femoral neck) were assessed using the DXA technique. The mean age of (DM) group was 59 ± 11.82 years, the height 1.55 ± 0.05 m., the weight 80.82 ± 13.25 kg, and BMI 33.81 ± 6.76 kg/m2. Results: The differences in measurements of the lumbar spine BMD (1.12 ± 0.13 g/cm2), total femur BMD (1.10± 0.17 g/cm2) neck of femur BMD (0.85± 0.35 g/cm2), and total BMD of the body (0.90± 0.06 g/cm2) were highly significant in healthy control group as compared to DM patients 0.84 ± 0.13 g/cm2, 0.99±0.15 g/cm2, 0.82± 0.24 g/cm2 and 0.79 ± 0.09 g/cm2 respectively. Conclusion: The results shows a highly significant in the lumbar spine, total femur, and total BMC, and not significant in the neck of the femur. The total body lean compartment was not significantly different between DM patients and healthy control women groups. The total body water compartment in the DM women group was highly significant lower different comparing with a healthy control group. The mathematical equations to predict total bone density in DM type 2 and healthy control women were calculated.

Effects of Low-dose Angiotensin II Infusion on Loop Segment Reabsorption: A Free-Flow Micropuncture Study in Rats

1995 ◽  
Vol 88 (3) ◽  
pp. 351-358 ◽  
Author(s):  
René Fransen ◽  
Walther H. Boer ◽  
Remmert De Roos ◽  
Peter Boer ◽  
Hein A. Koomans
Keyword(s):  
Angiotensin Ii ◽  
Proximal Tubule ◽  
Low Dose ◽  
Distal Tubule ◽  
Fractional Excretion ◽  
Free Flow ◽  
Control Group ◽  
Aortic Constriction ◽  
Micropuncture Study ◽  
Reabsorption Rate

1. Little direct information is available on the actions of angiotensin II beyond the proximal tubule. We therefore studied the effect of a mildly vasoconstrictive dose of angiotensin II on tubular handling of water, sodium (Na+) and lithium (Li+) in rats by means of free-flow micropuncture at the late proximal tubule and the early distal tubule. 2. Endogenous angiotensin II was suppressed by pretreament with enalapril. Compared with a control group, angiotensin II increased mean arterial pressure by 15 mmHg. Glomerular filtration rate decreased from 1.32 ± 0.05 to 1.10 ± 0.05 ml/min, Na+ excretion from 0.43 ± 0.09 to 0.13 ± 0.03 μmol/min, fractional delivery of water at the late proximal tubule from 50.1 ± 1.7 to 42.9 ± 3.2%, fractional delivery of Na+ at the late proximal tubule from 46.5 ± 1.3 to 39.1 ± 3.5% and fractional delivery of water at the early distal tubule from 26.4 ± 1.4 to 21.9 ± 1.0% (P < 0.05 for each variable). Fractional delivery of Na+ at the early distal tubule did not change significantly. 3. Similar experiments were performed during partial aortic constriction to exclude the effects of increased perfusion pressure. The data obtained were similar, except that in this group the fractional delivery of Na+ at the early distal tubule decreased from 8.6 ± 0.7 to 6.8 ± 0.9% (P < 0.05). 4. The relation between late proximal tubule Na+ delivery and Na+ reabsorption between late proximal and early distal tubule was not disturbed by angiotensin II. For water, however, this relation tended to shift to a higher reabsorption rate. 5. The decrease in fractional excretion of Li+ followed the decrease in proximal reabsorption as measured directly by micropuncture. Angiotensin II infusion did not appear to affect Li+ reabsorption beyond the proximal tubule. Distal fractional Na+ reabsorption estimated by the Li+ clearance increased significantly during angiotensin II infusion. 6. In conclusion, our data indicate that a Na+-retaining dose of angiotensin II increases Na+ reabsorption in the proximal tubule, an effect correctly indicated by the change in the fractional excretion of Li+, does not influence Na+ reabsorption in the loop of Henle beyond the proximal tubule, but may increase Na+ reabsorption in more distal segments.

Factors influencing body composition in persons with spinal cord injury: a cross-sectional study

2003 ◽  
Vol 95 (6) ◽  
pp. 2398-2407 ◽  
Author(s):  
Ann M. Spungen ◽  
Rodney H. Adkins ◽  
Charles A. Stewart ◽  
Jack Wang ◽  
Richard N. Pierson ◽  
...  
Keyword(s):  
Body Mass Index ◽  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Body Composition ◽  
Body Mass ◽  
Lean Mass ◽  
The Body ◽  
Control Group ◽  
Cord Injury ◽  
Total Body

To determine the body composition differences across age, 133 men with chronic spinal cord injury (SCI) (66 with tetraplegia, 67 with paraplegia) were compared with an age-, height-, and ethnicity-matched able-bodied male reference population ( n = 100) using two different dual-energy X-ray absorptiometry densitometers. The effects of duration of injury, level, and completeness of lesion were analyzed in the SCI population. Independent of age, total body and regional lean mass were lower and fat mass was higher in persons with SCI compared with controls. The SCI group was 13 ± 1% (means ± SE) fatter per unit of body mass index (kg/m2) compared with the control group ( P < 0.0001). Advancing age was strongly associated with less lean mass and greater adiposity in those with SCI, whereas it was mildly related in the controls. Total body and regional arm and trunk, but not leg, lean tissues were lower in subjects with SCI, across all ages, than in the controls. In summary, persons with SCI were fatter for any body mass index and demonstrated significantly less lean and more adipose tissues for any given age compared with controls.

Hormonal and electrolyte response to exposure to 17,500 ft

1975 ◽  
Vol 38 (4) ◽  
pp. 636-642 ◽  
Author(s):  
R. Frayser ◽  
I. D. Rennie ◽  
G. W. Gray ◽  
C. S. Houston
Keyword(s):  
Plasma Volume ◽  
Body Fluid ◽  
Plasma Renin ◽  
The Body ◽  
Potassium Excretion ◽  
The Third ◽  
Fluid Compartment ◽  
Response To Stress ◽  
Total Body ◽  
Sodium And Potassium

Hormone, electrolyte, and body fluid compartment changes were studied in subjects who either spent time at 10,000 ft before flying to 17,500 ft or were premedicated with acetazolamide and flown directly to 17,500 ft. In the former group, at 10,000 ft, renin and aldosterone were not different from control. Cortisol increased significantly from 9.8 to 19.5 mug/100 ml on the third day. At 17,500 ft, renin, aldosterone and cortisol were significantly elevated on day 3 but had returned to control levels by day 5. Sodium and potassium excretion was significantly reduced at both altitudes. Total body water, extracellular and plasma volume were reduced (P less than 0.05) at 17,500 ft. Subjects pretreated with acetazolamide and flown directly to 17,500 ft had significant increases (P less than 0.001) in plasma renin, aldosterone, and cortisol levels during the first 4 days at altitude. On day 1 there was a decrease of 45% in sodium and 38% in potassium excretion. On day 4 there was a decrease of 63% and 51%, respectively. These changes are not associated with the premedication. The initial changes may reflect the immediate response to stress and alkalosis followed by a return to control levels as the body adapts to altitude.

Effects of some probiotics during its use as a growth promoter in calves

2019 ◽  
Vol 20 (1) ◽  
pp. 62-66
Author(s):  
Magdy Amer
Keyword(s):  
Body Weight ◽  
Body Weight Gain ◽  
Total Body Weight ◽  
Treated Group ◽  
The Body ◽  
Control Group ◽  
Mean Corpuscular Hemoglobin ◽  
Growth Promoter ◽  
Probiotic Strains ◽  
Total Body

This study was performed on to evaluate the effect of some probiotic strains (Pediococcus acidophilus and Pedicoccus pentosaceus) on performance, blood picture and some biochemical parameters in serum of treated calves (10 weaned calves 90-115 kg). Calves were classified into 2 equal groups (each of 5 calves). The 1st group was served as the control group while the second group was given Maxboost® (20gm/head/day) in drinking water (after fermentation for 2-3 hours) for five months. Calves were weighed monthly to calculate the body weight gain till the end of the experiment whole blood weight and serum were collected from both groups at 1st, 2nd, 3rd, 4th and 5th month. Results revealed a significant increase in total body weight, body gain, total erythrocytes count, hemoglobin content, total leucocytes count, total protein and mean corpuscular hemoglobin. On the other hand, there were a significant decrease in serum aspartate transaminase (AST), serum alanine transaminase (ALT) and urea in pediococcus treated group compared to the control one.

Potassium and sodium excretion and potassium homeostasis during acute hypokalemia

1965 ◽  
Vol 208 (6) ◽  
pp. 1143-1152 ◽  
Author(s):  
Robert R. Siegel ◽  
William D. Lotspeich
Keyword(s):  
Sodium Excretion ◽  
Extracellular Fluid ◽  
Tubular Secretion ◽  
Urine Flow ◽  
Potassium Excretion ◽  
Distal Nephron ◽  
Close Coupling ◽  
Potassium Homeostasis ◽  
Blood Ph ◽  
Total Body

Decreased potassium and increased sodium excretion were observed in dogs acutely potassium-depleted by hemodialysis. Potassium excretion at constant blood pH varied directly with plasma [K+]. When filtered Na load and urine flow were constant during K+ depletion, increase in Na excretion was equivalent to decrease in K+ excretion, suggesting close coupling between transtubular movements of the two ions. Large changes in plasma [K+] (30%) and K+ excretion (50%) were produced with removal of a relatively small amount (estimated 3%) of total body K+. Plasma [K+] decrease during depletion was rapidly decelerated by movement of intracellular K+ into the extracellular fluid (ECF). When ECF [K+] stabilized, further decrease in K+ excretion ceased despite continued reduction of total body K+. It appears: 1) that tubular secretion of K+ is directly and rapidly responsive to reduction in ECF [K+]; 2) that low ECF [K+] may simultaneously impair contraluminal K+ uptake and Na extrusion, reducing K+ excretion and Na reabsorption during acute hypokalemia. Stoichiometry of changes suggests a 1:1 coupling between K+ secretion and moiety of Na reabsorption in the distal nephron.

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