Formation of glucocorticoids
These hormones of the adrenal cortex include glococorticoid, cortisol and cortisone. The hormones are formed from cholesterol via pregnenolone and progesterone as well as other intermediate stages. After release into the bloodstream, they are bound to the transport protein transcortin. The hormone receptors are located intracellularly in the cells of almost all organs.
Regulation of glucocorticoids
Glucocorticoids are part of a hypothalamic-pituitary control circuit. The hypothalamus forms CRH (Corticotropin Releasing Hormone), the pituitary gland forms ACTH (Adrenocorticotropic Hormone), which in turn promotes cortisol formation and release. The secretion of CRH is subject to a day-night rhythm with a maximum in the morning. In addition, stress and heavy physical work force its secretion. The release of ACTH is stimulated by CRH on the one hand, and by adrenaline on the other, and inhibited by cortisol in the sense of negative feedback.
Effect of glucocorticoids
The glucocorticoids are steroids and take over so-called catabolic tasks in the body. This means that they mobilize the body’s stored resources. They can be divided into natural, i.e. hormones produced by the body, and synthetic glucocorticoids, which are administered in drugs.
Both types act equally on almost all cells of the body. However, they have a particular effect on cells of the muscles, fatty tissue, liver, kidneys and skin. These organs contain most of the docking sites, i.e. receptors, for glucocorticoids.
They penetrate the cell wall and form a complex with their receptor. This complex has a direct influence on the DNA of the cell and can thus influence the formation of substances. This mechanism takes some time, which means that the desired effects of the glucocorticoids can only begin after 20 minutes to days.
There, they primarily promote the conversion of proteins and fats to sugar and continue to intervene in bone metabolism. One of the best known tasks of glucocorticoids is to contain inflammatory reactions. In doing so, they inhibit the release of the inflammatory and immune messenger substances from the cells, thereby reducing the typical symptoms such as redness, swelling, pain and warming. Glucocorticoids thus have an anti-allergenic effect and weaken the immune system (immunosuppressive).
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