The vital activity of any organism must occur in strict accordance with the conditions surrounding it. To do this, it is necessary to perceive, assimilate, properly process and respond to signals from the external environment. At the same time, the whole organism should work as a single whole, whose organs function in an orderly and consistent manner.
The neurohumoral system in the body is responsible for the orderliness and consistency of functions. It affects the systems and organs separately, exercising control over all the vital processes in the body. Thus, the integrity of the body is maintained.
Neurohumoral regulation is a form of control in which substances and nerve impulses carried by lymph and blood are links in a single process.
The functional state of the central nervous system is influenced by active chemicals circulating in the blood. So, for example, hormonal formation in the endocrine glands and its distribution into the blood occurs under the influence of the control of the nervous system.
Neurohumoral regulation is an integral part of the process of maintaining the internal constancy of the body and balancing it with the external environment. She also plays an important role in the processes of self-balancing physiological functions (automatically maintaining a strictly constant level of processes and constants in the body). Neurohumoral regulation combines humoral and nervous mechanisms, thus, being a more perfect form of balancing than each of them separately. The humoral link contributes to long-term regulatory influences. By means of the nerve link, rapid interaction between different sites is ensured.
Neurohumoral regulation of body functions is performed in two ways. The first method includes the direct action of hormones or metabolic products in the tissues of the central nervous system. In this case, a change in the excitability of nerve cells occurs. For example, carbon dioxide in the blood acts on the cells of the respiratory system, and the irritation of the cells of the food system is carried out by the chemical composition of the blood. Neurohumoral regulation is also carried out by exposure to various substances carried through the body with the help of blood on special receptors of internal organs. They begin to respond to changes in the chemical composition and osmotic pressure of liquids. So, for example, together with the cells of the respiratory system, chemoreceptors of the vascular walls react to a change in the carbon dioxide content in the blood.
A large number of specific and nonspecific metabolic products (metabolites) take part in neurohumoral regulation. These include gastrointestinal and tissue hormones, histamine, hypothalamic neurohormones, a wide range of oligopeptides, prostaglandins. Through the bloodstream, they spread throughout the body. However, they cause specific reactions only in the "resulting organs" upon entering into contact with their receptors.
The state of the nervous and humoral systems in the body is determined by the level of biologically active products in secretions and liquid media. In this case, radioimmunological analysis, immunocytochemistry, histochemistry, ultrastructural analysis are widely used. The constant change in the quantitative and qualitative ratios of biologically active products reflects and determines the reactivity and tone of both the central and peripheral departments in the nervous system, and also determines the vital activity of the whole organism as a whole. The dynamics of regulatory processes depends mainly on external stimuli and on the needs of the body.