The adrenal glands are paired glands of internal secretion. They are located above the upper parts of the kidneys in the region of 11-12 thoracic vertebrae. The function of the adrenal glands in the human body is the production and release into the blood of a number of the most important hormones necessary to maintain normal functioning.
Adrenal gland structure
The left adrenal gland in an adult has a lunar shape, the right - triangular. Both adrenal glands are enclosed in a thin fibrous capsule. In length they reach 7 cm, in width - 3.5 cm. Thickness reaches 8 mm. Their mass averages about 14 g. From the adrenal glands bundles of connective tissue with nerves and blood vessels depart. Blood flows through three groups of arteries, and its outflow occurs through the central and superficial veins. In the organ itself, 2 parts are distinguished. The outer part consists of cortical matter and accounts for 90% of the total mass of the adrenal glands. The cortical region, in turn, is divided into 3 zones: glomerular, fascicular, and mesh. It implements the functions of the adrenal glands in the production of steroid, corticosteroid and sex hormones. Inside, the organ is filled with brain matter and contains many nerve cells. The basis of the substance is chromaffin cells. These cells provide the function of the adrenal glands to produce catecholamine hormones: dopamine, norepinephrine and adrenaline.
The importance of the adrenal glands for metabolism in the human body
The adrenal glands secrete a number of hormones that regulate metabolic processes. For example, glucocorticoid hormones promote carbohydrate metabolism in the body. With an excess of them, diabetes can develop. Decay of adipose tissue is also regulated. Hormones produced by the adrenal glands control the amount and location of its deposition.
The functions of the adrenal glands in the regulation of water-salt balance
Thanks to these glands, control is maintained over the retention of water in the body and the implementation of mineral metabolism. This process is closely associated with the work of the kidneys and the substances that are synthesized in them. Any violations in this system are fraught with the accumulation of excess fluid, increased blood pressure, as well as damage to the kidneys.
The functions of the adrenal glands in the production of sex hormones
Androgens and estrogens â male and female sex hormones â are formed in the cortex of the paired glands under consideration. They affect reproductive function, and are also important for the formation of secondary sexual characteristics. For example, androgens affect hair growth and support the function of the sebaceous glands in the body.
Functions of the human adrenal gland in adapting the body to stressful conditions
These functions consist in the development of special neurotransmitters (adrenaline, norepinephrine), which affect the work of the sympathetic nervous system, participating in conducting impulses. Thus, these hormones contribute to the restructuring of the body in a state of stress. They increase pulse and blood pressure, increase perspiration, reduce the motility of the gastrointestinal tract, and stimulate the expansion of the bronchi.