Adrenal hormones and their synthetic analogues
The mammalian and human adrenal cortex produces a large amount of steroid hormones called corticosteroids.
They are derived from pregnane and can be chemically divided into 11-deoxysteroids, 11-hydroxysteroids and 11, 17-hydroxy-steroids. The first group includes deoxycorticosterone, which does not have an oxygen atom in position 11 of the steroid nucleus. Group 11, 17-oxysteroids include cortisol (hydrocortisone) and cortisone. These substances are isolated from the adrenal cortex in crystalline form.
For use as a medicine, corticosteroids are currently produced synthetically. A number of synthetic drugs are widely used in medical practice.
Endogenous hormones of the adrenal cortex are essential for human and animal life. Animals die several days after adrenal gland removal (adrenectomy). Acute adrenal insufficiency is accompanied by thickening of the blood, lowering blood pressure, gastrointestinal disorders, asthenia, lowering body temperature and basal metabolic rate; there is also a loss of sodium and potassium retention, hypoglycemia, a delay in the blood of nitrogenous substances. The introduction of corticosteroids to adrenectomized animals (especially with the simultaneous introduction of sodium chloride and water) leads to the disappearance of pathological phenomena and the preservation of life.
According to the effect on metabolism, the main corticosteroids are divided into two groups: mineralocorticosteroids and glucocorticosteroids, or mineralocorticoids and glucocorticoids.
The main representatives of the first group are aldosterone and deoxycorticosterone. These hormones actively affect the exchange of electrolytes and water and relatively little - on carbohydrate and protein metabolism. Of the drugs belonging to the mineracorticosteroid group, deoxycorticosterone acetate (DOXA) is the most widely used in medical practice.
The main endogenous (natural) glucocorticosteroids are cortisol (hydrocortisone) and cortisone. They actively influence carbohydrate and protein metabolism, but are less active in relation to water and salt metabolism. Contribute to the accumulation of glycogen in the liver, increase blood glucose, cause an increase in nitrogen excretion in the urine.
Under the influence of glucocorticosteroids, the pattern of red and white blood changes, eosinopenia, lymphopenia and neutrophilia develop.
Glucocorticosteroids have anti-inflammatory, desensitizing and anti-allergic effects. They also have anti-shock and anti-toxic properties.
Characteristic of glucocorticosteroids is their immunosuppressive activity. Unlike cytostatics, the immunosuppressive properties of glucocorticosteroids are not associated with the mitostatic effect.
Their immunosuppressive effect is the total result of the suppression of different stages of immunogenesis: the migration of stem cells (bone marrow), the migration of B cells, and the interaction of T and B lymphocytes.
According to modern data, corticosteroids inhibit the release of cytokinins (interleukins 1 and 2 and interferon) from lymphocytes and macrophages, inhibit the release of inflammatory mediators by eosinophils, reduce arachidonic acid metabolism (see Prostaglandins). Stimulating steroid receptors, they induce the formation of a special class of lipocortin proteins with anti-edematous activity.
In relatively large doses, glucocorticosteroids inhibit the development of lymphoid and connective tissue, including reticuloendothelium; reduce the number of mast cells that are the place of formation of hyaluronic acid; inhibit the activity of hyaluronidase and help reduce capillary permeability. Under the influence of glucocorticosteroids, synthesis is delayed and the breakdown of proteins is accelerated.
The production of adrenal hormones is controlled by the central nervous system and is closely related to the function of the pituitary gland. Adrenocorticotropic hormone of the pituitary (ACTH; corticotropin - see) is a physiological stimulator of the adrenal cortex; without it, the normal function of the adrenal cortex is impossible. With various adverse effects causing a state of tension (stress) in the body, the functions of the pituitary gland are enhanced, accompanied by the release of an increased amount of corticotropin and stimulation of the function of the adrenal cortex. Corticotropin enhances mainly the formation and release of glucocorticosteroids. The latter in turn affect the pituitary gland, inhibiting the production of corticotropin and thus reducing the further excitation of the adrenal glands. Prolonged introduction into the body of glucocorticosteroids (cortisone and its analogues) can lead to inhibition and atrophy of the adrenal cortex, as well as to the inhibition of the formation of gonadotropic and thyrotropic hormones of the pituitary gland.
From natural glucocorticosteroids, cortisone, hydrocortisone and deoxycorticosterone, which are obtained by synthetic means, have found practical application as medicines. A number of synthetic analogues of cortisone and hydrocortisone (prednisone, prednisone, dexamethasone, etc.), which have found wide application, have been obtained. These compounds are more active than natural glucocorticosteroids, act in smaller doses, have a weaker effect on mineral metabolism; Some of them (mainly fluorinated derivatives) are more convenient for local use, since they are less absorbed. Synthetic analogues are now almost completely replaced by cortisone.
The main indications for the use of glucocorticosteroids are collagenosis, rheumatism, rheumatoid arthritis (infectious non-specific polyarthritis), bronchial asthma, acute lymphoblastic and myeloblastic leukemia, infectious mononucleosis, neurodermatitis, eczema and other skin diseases, various allergic diseases. Glucocorticosteroids are also used in Addison's disease, acute hormonal insufficiency of the adrenal cortex, hemolytic anemia, glomerulonephritis, acute pancreatitis, viral hepatitis and other diseases. In connection with the anti-shock effect, glucocorticosteroids are prescribed for the prevention and treatment of shock (post-traumatic, surgical, toxic, anaphylactic, burn, cardiogenic, etc.).
The immunosuppressive effect of glucocorticosteroids allows them to be used in the transplantation of organs and tissues to suppress the rejection reaction, as well as in various so-called autoimmune diseases.
Glucocorticosteroids are in many cases highly valuable therapeutic agents. However, it is necessary to take into account that they can cause a number of side effects, including the Itsenko Cushing's symptom complex (sodium retention and water in the body with the possible appearance of edema, increased potassium excretion, increased blood pressure); hyperglycemia up to diabetes mellitus (steroid diabetes); increased calcium excretion and osteoporosis; slowing down the regeneration processes; exacerbation of gastric ulcer and duodenal ulcer, ulceration of the digestive tract, perforation of an unrecognized ulcer, hemorrhagic pancreatitis, decrease in resistance to infections; increased blood clotting with the possibility of blood clots; the appearance of acne, moonlike face, obesity, menstrual disorders, etc.
Nervous and mental disorders are also possible: insomnia, agitation (with the development of psychosis in some cases), epileptiform convulsions, euphoria.
Some side effects (especially those associated with sodium and water retention in the body) are less pronounced with the use of synthetic glucocorticosteroids (triamcinolone, dexamethasone, etc.) due to their smaller mineralocorticoid action.
With long-term use of glucocorticosteroids should consider the possibility of inhibition of the function of the adrenal cortex with the suppression of the biosynthesis of hormones; Atrophy of the adrenal glands is not excluded. The introduction of corticotropin simultaneously with glucocorticosteroids prevents atrophy of the adrenal glands.
The sudden cessation of glucocorticosteroids can cause an exacerbation of the process. End of treatment should be done by gradually reducing the dose. Within 3 to 4 days after discontinuation of the drug, small doses of corticotropin are prescribed (10 to 20 U per day) to stimulate the function of the adrenal cortex.
The frequency and strength of side effects caused by glucocorticosteroids can be expressed in varying degrees. With the right choice of dose, the necessary precautions, careful monitoring of the course of treatment, there may be no side effects.
In connection with a possible side effect, glucocorticosteroids should be used only if there are clear indications and under close medical supervision.
To reduce side effects during treatment with glucocorticosteroids, a sufficient amount of complete protein should be introduced into the body, reduce the introduction of chlorides and increase the proportion of potassium (1, 5 - 2 g per day). It is necessary to constantly monitor the level of blood pressure, glucose in the blood, blood clotting, diuresis and body weight of the patient.
Contraindications to the use of glucocorticosteroids coincide mainly with contraindications to the use of corticotropin (see).
Preparations containing glucocorticosteroids (ointments, drops) should not be used for viral diseases of the eyes and skin (including preparations with the addition of antibacterial agents), since in connection with the suppression of regeneration processes, the formation of common ulcers up to perforation of the cornea is possible.
Ointments containing corticosteroids should not be used for fungal and parasitic skin lesions, unless special anti-fungal or antiparasitic agents are added to these ointments (see Mikozolon).
All drugs glucocorticosteroids retain with caution (list B), protected from light.
Subgroup Hormones, their analogues and antihormonal drugs include drugs:
- Alclometasone (Alclometasone)
- Arfazetin (Arfasetinum)
- Beclomethasone dipropionate (Beclometasoni dipropionas)
- Betamethasone (Betamethasonum)
- Budesonide (Budesonidum)
- Halometasone (Halometasone)
- Hydrocortisone (Hydrocortisonum)
- Hydrocortisone Acetate (Hydrocortisoni acetas)
- Hydrocortisone hemisuccinate (Hydrocortisoni hemisuccinas)
- Deoxycorticosterone Acetate (Desoxycorticosteroni acetas)
- Deoxycorticosterone Trimethyl Acetate (Desoxycorticosteroni trimethylacetas)
- Dexamethasone (Dexamethasonum)
- Clobetasol (Clobetasol)
- Cortisone (Cortisonum)
- Methylprednisolone (Methylprednisolonum)
- Methylprednisolone aceponate (Methylprednisolone aceponate)
- Prednisolone (Prednisolonum)
- Prednisolone hemisuccinate (Prednisolon hemisuccinas)
- Sinaflan (Synaflanum)
- Triamcinolone (Triamcinolonum)
- Triamcinolone acetonide (Triamcinoloni acetonidum)
- Ultralan (Ultralan)
- Fludrocortisone (Fludrocortisone)
- Flumethasone Pivalate (Flumethasoni pivalas)
- Fluticasone (Flunicasone)