Mineral metabolism

Mineral metabolism (salt exchange) - a set flowing in the body of the processes of absorption, distribution, transformation and excretion of inorganic salts.
The main part of inorganic salts are chlorides, phosphates, sulphates and carbonates potassium, sodium, calcium and magnesium. Mineral metabolism plays the role of a regulator of a number of physico-chemical processes in the body, for example in the maintenance of a constant osmotic pressure of body fluids, stabilize the pH of the blood and tissues, regulating the permeability of cell membranes and other Ions of some salts are activators and inhibitors of enzymes (see). The absorption of inorganic substances occurs primarily in the small intestine; to different bodies they are carried by the blood and lymph. The main depot of calcium and magnesium is a bone fabric, sodium and potassium - skin, most salt - liver. The selection of inorganic salts from the body is through the kidneys, intestines and skin. Violation of mineral metabolism, such as lack of food some salts may cause severe pathological phenomena in the body.
Cm. also trace elements, minerals, Metabolism and energy.

Mineral metabolism is the complex of processes of absorption, distribution, transformation and excretion from the body of inorganic compounds. The main part of these compounds in humans are chloride, sulphate, phosphate and carbonate salts of potassium, sodium, calcium and magnesium. In adults, weighing 70 kg), the total amount of ash in the body is about 3 kg, of which the share of calcium is 39%, phosphorus - 22%, sulfur - 4%, chlorine - 3%, potassium - 5%, sodium - 2% and magnesium - 0,7%. The relatively high content of calcium and phosphorus in the ash due to the fact that these elements in the form of various salts calcium phosphate constitute the prevailing part of the skeleton. The content of the above elements in whole blood is (mg%): sodium - 175, potassium - 210, calcium 5 mg - 4,3, chlorine - 280, inorganic phosphorus - 3,5, inorganic sulfur - 1; in the serum of adults corresponding value is equal: sodium - 335 ±10, potassium - 20 yo 2, calcium - 10±0,3, magnesium - 2,4± ±0,7, chlorine - 365±15, inorganic phosphorus - 3,7 ±0,8, inorganic sulfur - 1,3 ±of 0.5. In addition to the above elements, which are typically designated as macronutrients, in humans can detect almost all other chemical elements, but they are in dense tissue and blood only in very small quantities (share mg%) and only a small part of them is the true bio-elements, i.e. elements necessary for normal functioning of the vital processes of the organism. Among those elements, referred to as micronutrients (see), belong iron, copper, zinc, manganese, cobalt, molybdenum, iodine and fluorine. Relative to other (mercury, arsenic, aluminum, Nickel, titanium) has no data that would demonstrate that they have any physiological value. Part of microelements enters the body and with the inhaled air.
Unlike exchange of organic compounds, mineral metabolism has no energy value and the value of its plastic (with the exception of the role of calcium, phosphorus and magnesium in the formation of bone system) is very limited. Despite this, mineral starving animals, i.e. lack of food one or many of true Bioelements, quickly cause severe pathological phenomena, and then the death of animals. This is a consequence of the fact that inorganic compounds tissues and body fluids play an important role as bioregulators of the main processes of metabolism in the body. So, for example, ions of sodium, potassium and chlorine are the main regulators of osmotic pressure of the blood, spinal fluid, lymph, intra - and intercellular tissue fluids and any disturbance to their normal ratios causes significant changes in the distribution of water between the dense tissues and body fluids. The ratio of the total quantity of inorganic cations and anions largely depends on the pH of the tissues and blood and the possibility of
changes in one direction or another in various pathological conditions. Not less important is the fact that ions of calcium, potassium, sodium, manganese, magnesium, etc. are powerful activators, and in some cases inhibitors of many enzymes. A number of trace elements (copper, molybdenum, zinc) is part of the active site of a number of enzymes, and iron is an indispensable part of the hemoglobins and cytochromes. Calcium and phosphorus necessary for the processes of ossification; in addition, inorganic phosphorus is the main source of formation of adenosine triphosphate (ATP) and many organic phosphorus compounds, which is the most important carriers of energy, and inorganic sulfur - source for the formation of a number of serosoderzhashchikh organic compounds.
Thus, the persistence of the concentration of inorganic compounds in organs and tissues is essential for normal metabolism of organic compounds.
Cm. also the Metabolism and energy.