The biological role of alkali metals is enormous, as their content in the body clearly demonstrates: the potassium content is 250 g, and sodium — 70 g (per 70 kg of body weight).
Sodium is the main extracellular ion, and potassium is the main intracellular ion. Osmotic pressure of blood plasma is maintained at the required level due to NaCl. The relationship of these ions in the body plays an important role in maintaining the isotonicity of the cells. Thus, when NaCl is deficient in the body, disorders of the nervous system, circulatory system, smooth muscle and skeletal muscles are observed.
Potassium ion, like sodium, plays an important role in regulating body functions. Suffice it to say that the excitability and conductivity of the heart muscle are directly dependent on the content of K + ions: a high concentration inhibits the automatism and contractility of the heart muscle, and a decrease in the serum ion content in serum leads to severe rhythm disturbances in the heart. Potassium is also involved in the processes of nerve impulses and their transfer to innervated organs.
Medicine has accumulated significant information about the role of lithium ions in the body. It has been established, for example, that some lithium compounds have a very favorable effect in the treatment of diseases associated with mental disorders. It has been proven that lithium is able to regulate the activity of enzymes involved in the transfer of Na + and K ions from the intercellular fluid into brain cells, while significantly affecting the ionic balance of the cell. Therefore, by aligning the sodium-potassium balance, lithium salts have a favorable effect. effect in the treatment of patients suffering from mental disorders.
In medical practice, the following inorganic compounds of alkali metals have found wide application.
Sodium chloride (sodium chloride) NaCl. 0.9% aqueous solution is called isotonic solution. It is used for large losses of fluid by the body. Hypertonic solutions (3, 5 and 10%) are used externally in inflammatory processes.
Sodium Bicarbonate NaHCO; j (sodium bicarbonate – drinking soda) is used in medical practice as an antiseptic due to its ability to create an alkaline reaction in solutions due to hydrolysis. It is administered orally with an increased acidity of gastric juice, and also forms part of the combination drugs intended for the treatment of gastrointestinal diseases.
Sodium Bromide NaBr and potassium bromide KBG (sodium bromide and potassium bromide) are used in medicine as sedatives, since these drugs normalize the violation of the ratio between the processes of excitation and inhibition in the cerebral cortex.
Sodium iodide (sodium iodide) Nal is used in the treatment of diseases of the thyroid gland. Ingestion of large doses of elemental iodine is fraught with dangerous consequences, therefore, Nal is used instead.
The body of an adult per day consumes potassium on average 2–3 mg per 1 kg of weight, and in children this number is six times more — 12–13 mg per 1 kg of weight. A person receives most of the potassium he needs from plant poorness. Potassium is one of the elements necessary for plant life, as it regulates growth, development, water-salt metabolism, nitrogen metabolism and respiration. The absence of potassium in sufficient quantities leads to the death of the plant.
Potash fertilizers are commonly used to replenish soil with potassium, of which sylvin KC1 is the most important.