The human endocrine system , along with the nervous system, controls the vital processes in the body, providing them with the so-called humoral regulation and maintaining homeostasis in it, i.e. internal balance. Similar internal mechanisms in medicine are studied in detail by the science of endocrinology. A feature of organs that are united by the concept of "human endocrine system" is that they do not have excretory ducts into the body cavity. They deliver the result of their secretion, otherwise hormones, directly into the blood and lymphatic fluid, unlike exocrine glands that communicate with various body cavities, as well as the external environment.
The endocrine system of a person differs from other systems of the body in its “distantness”. This means that the control of the body on its part is carried out not in the places of production of such active substances as hormones, but very far from them. For example, the antidiuretic hormone is produced in the pituitary gland, which is located in the cranium, and has an effect on the renal tubules. Same thing with oxytocin. It is also a product of the neurohypophysial zone located in the cranial cavity, and the main place of its application is the muscles of the uterus.
Each person’s endocrine system has its own hierarchical ladder. All the internal glands producing their specific hormones are subject to the influence of the hypothalamic-pituitary system, which is directly controlled by the nervous activity and cortical structures of the brain. The pituitary gland is the connecting link between the glands of the lower level and the hypothalamus. The latter, perceiving a signal from the nervous system, produces “releasing hormones” (statins and liberins), which affect the pituitary cells and cause them to either increase secretion or decrease secretion of tropic hormones. Tropic hormones of the adenohypophysis directly affect the final gland. For example, thyroid-stimulating hormone acts only on the glandular tissue of the thyroid gland, and lactotropic hormone on the mammary glands. The end of this sequential regulation is the production of appropriate hormones, which through blood and lymph affect the metabolism, growth, nutrition and development of other organs and systems.
By their chemical structure, all hormones can be divided into four main groups: glycoprotein, protein-peptide, steroid and amino acid. They can also be (as discussed above) divided by their physical action. Hypothalamic and pituitary hormones belong to starting hormones, and all the rest to performers. Launchers regulate the work of hormones-performers.
Diseases of the endocrine system dramatically disrupt the balance established in the body. The corresponding clinical picture will depend on the level of damage. The nature of the abnormal secretion of biological substances can also affect it. The pathophysiology of the endocrine system in its various diseases is such that if a decrease in the secretion of a hormone is observed in the body, then clinically this will look like its acute deficiency, and, accordingly, vice versa. An example is myxedema or hypothyroidism, when thyroid function is significantly reduced, and its direct opposite is thyrotoxic goiter during hyperproduction of thyroid hormones.
The human endocrine system, despite the successful and rapid development of medicine and nanotechnology, is still not a fully studied field of anatomy and physiology. However, what science already knows allows endocrinologists to actively engage in the treatment and prevention of its pathological conditions, making patients' lives more comfortable and better.