Sodium performs which function

Some insulin-dependent diabetic patients experience a relative reduction of potassium in the blood from the redistribution of potassium. When insulin is administered and glucose is taken up by cells, potassium passes through the cell membrane along with glucose, decreasing the amount of potassium in the blood and IF, which can cause hyperpolarization of the cell membranes of neurons, reducing their responses to stimuli.

Hyperkalemia , an elevated potassium blood level, also can impair the function of skeletal muscles, the nervous system, and the heart. Hyperkalemia can result from increased dietary intake of potassium. In such a situation, potassium from the blood ends up in the ECF in abnormally high concentrations. This can result in a partial depolarization excitation of the plasma membrane of skeletal muscle fibers, neurons, and cardiac cells of the heart, and can also lead to an inability of cells to repolarize.

Because of such effects on the nervous system, a person with hyperkalemia may also exhibit mental confusion, numbness, and weakened respiratory muscles. Chloride is the predominant extracellular anion. Chloride is a major contributor to the osmotic pressure gradient between the ICF and ECF, and plays an important role in maintaining proper hydration. Chloride functions to balance cations in the ECF, maintaining the electrical neutrality of this fluid. The paths of secretion and reabsorption of chloride ions in the renal system follow the paths of sodium ions.

Hypochloremia , or lower-than-normal blood chloride levels, can occur because of defective renal tubular absorption. Vomiting, diarrhea, and metabolic acidosis can also lead to hypochloremia. Hyperchloremia , or higher-than-normal blood chloride levels, can occur due to dehydration, excessive intake of dietary salt NaCl or swallowing of sea water, aspirin intoxication, congestive heart failure, and the hereditary, chronic lung disease, cystic fibrosis.

In people who have cystic fibrosis, chloride levels in sweat are two to five times those of normal levels, and analysis of sweat is often used in the diagnosis of the disease.

Watch this video to see an explanation of the effect of seawater on humans. What effect does drinking seawater have on the body? Bicarbonate is the second most abundant anion in the blood. This role will be discussed in a different section.

Bicarbonate ions result from a chemical reaction that starts with carbon dioxide CO 2 and water, two molecules that are produced at the end of aerobic metabolism.

Only a small amount of CO 2 can be dissolved in body fluids. Thus, over 90 percent of the CO 2 is converted into bicarbonate ions, HCO 3 — , through the following reactions:. The bidirectional arrows indicate that the reactions can go in either direction, depending on the concentrations of the reactants and products.

Carbon dioxide is produced in large amounts in tissues that have a high metabolic rate. Carbon dioxide is converted into bicarbonate in the cytoplasm of red blood cells through the action of an enzyme called carbonic anhydrase.

Bicarbonate is transported in the blood. Once in the lungs, the reactions reverse direction, and CO 2 is regenerated from bicarbonate to be exhaled as metabolic waste. About two pounds of calcium in your body are bound up in bone, which provides hardness to the bone and serves as a mineral reserve for calcium and its salts for the rest of the tissues. Teeth also have a high concentration of calcium within them.

A little more than one-half of blood calcium is bound to proteins, leaving the rest in its ionized form. In addition, calcium helps to stabilize cell membranes and is essential for the release of neurotransmitters from neurons and of hormones from endocrine glands. Calcium is absorbed through the intestines under the influence of activated vitamin D.

A deficiency of vitamin D leads to a decrease in absorbed calcium and, eventually, a depletion of calcium stores from the skeletal system, potentially leading to rickets in children and osteomalacia in adults, contributing to osteoporosis. Hypocalcemia , or abnormally low calcium blood levels, is seen in hypoparathyroidism, which may follow the removal of the thyroid gland, because the four nodules of the parathyroid gland are embedded in it. Hypercalcemia , or abnormally high calcium blood levels, is seen in primary hyperparathyroidism.

Some malignancies may also result in hypercalcemia. Phosphate is found in phospholipids, such as those that make up the cell membrane, and in ATP, nucleotides, and buffers. Hypophosphatemia , or abnormally low phosphate blood levels, occurs with heavy use of antacids, during alcohol withdrawal, and during malnourishment. In the face of phosphate depletion, the kidneys usually conserve phosphate, but during starvation, this conservation is impaired greatly.

Hyperphosphatemia , or abnormally increased levels of phosphates in the blood, occurs if there is decreased renal function or in cases of acute lymphocytic leukemia. Additionally, because phosphate is a major constituent of the ICF, any significant destruction of cells can result in dumping of phosphate into the ECF. Sodium is reabsorbed from the renal filtrate, and potassium is excreted into the filtrate in the renal collecting tubule.

Drugs: Many older people take drugs for high blood pressure High Blood Pressure High blood pressure hypertension is persistently high pressure in the arteries. Often no cause for high blood pressure can be identified, but sometimes it occurs as a result of an underlying Urination and thirst are The above situations can result in losing fluid or not consuming enough fluid and thus can cause a high sodium level in blood hypernatremia Hypernatremia High Level of Sodium in the Blood In hypernatremia, the level of sodium in blood is too high.

Vomiting, diarrhea, excessive sweating, burns, kidney failure, and use of diuretics may cause dehydration. People feel thirsty, and as dehydration Because these situations are more common among older people, hypernatremia is also more common among them. Hypernatremia is poorly tolerated by older people and can result in confusion, coma, and death if severe.

Excess fluid and sodium also occur more commonly in older people because disorders that usually result in excess fluid fluid overload Overhydration Overhydration is an excess of water in the body. A low sodium level in blood hyponatremia Hyponatremia Low Level of Sodium in the Blood In hyponatremia, the level of sodium in blood is too low. Hyponatremia usually results when the body retains too much fluid, as occurs in heart failure or liver disease.

Hyponatremia also occurs in older people who take certain types of diuretics thiazide diuretics such as hydrochlorothiazide , particularly if the kidneys are not functioning normally. Diuretics, which are sometimes called water pills, are drugs that help the body eliminate excess fluid.

Using liquid nutritional supplements or receiving intravenous fluids that are low in sodium while in the hospital also may cause hyponatremia in older people. Merck and Co. From developing new therapies that treat and prevent disease to helping people in need, we are committed to improving health and well-being around the world.

The Manual was first published in as a service to the community. Learn more about our commitment to Global Medical Knowledge. This site complies with the HONcode standard for trustworthy health information: verify here. Common Health Topics. Controlling blood volume. Maintaining fluid and sodium balance in older people. Electrolyte Balance. The reabsorption of potassium takes place at the proximal convoluted tubule and thick ascending loop of Henle. Potassium secretion occurs at the distal convoluted tubule.

Aldosterone increases potassium secretion. Potassium channels and potassium-chloride cotransporters at the apical membrane also secrete potassium. Potassium disorders are related to cardiac arrhythmias.

Hypokalemia occurs when serum potassium levels under 3. Hyperkalemia occurs when the serum potassium levels are above 5.

Muscle cramps, muscle weakness, rhabdomyolysis, myoglobinuria are presenting signs and symptoms in hyperkalemia. Calcium has a significant physiological role in the body. It is involved in skeletal mineralization, contraction of muscles, the transmission of nerve impulses, blood clotting, and secretion of hormones. The diet is the predominant source of calcium. It is mostly present in the extracellular fluid.

Absorption of calcium in the intestine is primarily under the control of the hormonally active form of vitamin D, which is 1,dihydroxy vitamin D3.

Parathyroid hormone also regulates calcium secretion in the distal tubule of kidneys. Calcitonin acts on bone cells to increase the calcium levels in the blood. Hypocalcemia diagnosis requires checking the serum albumin level to correct for total calcium, and the diagnosis is when the corrected serum total calcium levels are less than 8.

CHecking serum calcium levels is a recommended test in post-thyroidectomy patients. Hypercalcemia is when corrected serum total calcium levels exceed Humoral hypercalcemia presents in malignancy, primarily due to PTHrP secretion. The acid-base status of the blood drives bicarbonate levels. The kidneys predominantly regulate bicarbonate concentration and are responsible for maintaining the acid-base balance. Kidneys reabsorb the filtered bicarbonate and also generate new bicarbonate by net acid excretion, which occurs by excretion of both titrable acid and ammonia.