Regulatory mechanisms for maintaining homeostasis of sodium ions

Abstract

According to general scientific recognition, the content of sodium ions in the body of a healthy person is quite constant, and among the multifaceted biological functions of this electrolyte, participation in maintaining water-salt homeostasis is the most important. Deviations from the normal level of concentration of sodium ions in the blood plasma are the most common electrolyte balance disorders in clinical medicine; however, dysionias still remain a relevant subject of research, in particular, their pathogenetic aspects and the possibilities of pharmacological correction. Sodium as an electrolyte is essential for the vo­lume of extracellular fluid the content of which is inversely related to the urinary excretion of sodium ions. Sodium homeostasis is tightly regulated. In the reactions of ensuring the sodium balance in the body, the kidneys play a leading role, and the changes in their functional state are mediated through the action of the basic neurohumoral regulatory systems. The main renal homeostatic processes — glomerular filtration, tubular reabsorption and secretion — are of decisive importance for the removal of excess ions of sodium or its retention in the body. At the same time, it was found that there are also extrarenal mechanisms that are still being studied. Moreover, a number of studies have suggested that sodium ions can be stored in body tissues without adequate retention of water to buffer the electrolyte. Given the participation of the kidneys in maintaining normal functional and metabolic relationships and in pathological syndromes related to other organs, it is possible to predict the correlation of the activity of established and new markers of extrarenal mechanisms with reducers of water-electrolyte exchange the final effects of which are mediated through changes in the functional state of the kidneys. Evaluation of additional sodium-regulatory systems is a promising current direction for expanding ideas about mechanisms of stability of electrolytes and water.