Cortisol
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Cortisol
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| Systematic (IUPAC) name | |
| 11,17,21-trihydroxy-,(11beta)- pregn-4-ene-3,20-dione |
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| Identifiers | |
| CAS number | 50-23-7 |
| ATC code | H02AB09 (and others) |
| PubChem | 5754 |
| Chemical data | |
| Formula | ? |
| Mol. weight | 362.465 |
| Pharmacokinetic data | |
| Bioavailability | ? |
| Metabolism | ? |
| Half life | ? |
| Excretion | ? |
| Therapeutic considerations | |
| Pregnancy cat. |
C |
| Legal status | |
| Routes | Oral tablets, intravenously, topical |
Cortisol is a corticosteroid hormone produced by the adrenal cortex that is involved in the response to stress; it increases blood pressure, blood sugar levels, may cause infertility in women, and suppresses the immune system. In pharmacology, cortisol is referred to as Hydrocortisone, and is used to treat allergies and inflammation.
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[edit] Synthesis
Cortisol is synthesized from pregnenolone. The change involves hydroxylation of C-11, C-17, and C-21, the oxidation of C-3, and the isomerization of the C-5 double bond to C-4. The synthesis takes place in the zona fasciculata of the cortex of the adrenal glands. (The name cortisol comes from cortex.) While the adrenal cortex also produces aldosterone (in the zona glomerulosa) and some sex hormones (in the zona reticulosa), cortisol is its main secretion. The medulla of the adrenal gland lies under the cortex and mainly secretes adrenaline and noradrenaline under sympathetic stimulation.
The synthesis of cortisol in the adrenal gland is stimulated by the anterior lobe of the pituitary gland with adrenocorticotropic hormone (ACTH); production of ACTH is in turn stimulated by corticotropin-releasing hormone (CRH), released by the hypothalamus.
[edit] Physiology
The amount of cortisol present in the serum undergoes diurnal variation, with the highest levels present in the early morning, and lower levels in the evening, several hours after the onset of sleep. Information about the light/dark cycle is transmitted from the retina to the paired suprachiasmatic nuclei in the hypothalamus. Changed patterns of serum cortisol levels have been observed in connection with abnormal ACTH levels, clinical depression, psychological stress, and such physiological stressors as hypoglycemia, illness, fever, trauma, surgery, fear, pain, physical exertion or extremes of temperature. There is also significant individual variation, although a given person tends to have consistent rhythms.
Cortisol also inhibits the secretion of corticotropin releasing hormone (CRH), resulting in feedback inhibition of ACTH secretion. Some researchers believe that this normal feedback system may break down when animals are exposed to chronic stress.
In normal release, cortisol has widespread actions which help restore homeostasis after stress. It acts as a physiological antagonist to insulin by promoting gluconeogenesis, breakdown of lipids, and proteins, and mobilization of extrahepatic amino acids and ketone bodies. This leads to increased blood glucose concentrations, resulting in increased glycogen formation in the liver (Freeman, 2002). It also increases blood pressure. The hormone lowers the activity of the immune system in the blood. Cortisol prevents proliferation of T-cells by rendering the interleukin-2 producer T-cells unresponsive to interleukin-1 (IL-1), and unable to produce the T-cell growth factor (Palacios)Isoptera 22:03, 11 December 2006 (UTC) = Isoptera. It reflects leukocyte redistribution to lymph nodes, bone marrow, and skin (Cohen, 1972; Cox & Ford, 1982; Dhabhar & McEwen, 1996; Dhabhar and Dhabhar; Fauci, 1975; Fauci & Dale, 1974; Fauci & Dale, 1975; Yu et al., 1974). Acute administration of corticosterone (the endogenous Type I and Type II receptor agonist), or RU28362 (a specific Type II receptor agonist), to adrenalectomized animals induced changes in leukocyte distribution. Bone formation is also lowered by cortisol. Cortisol moves potassium out of cells in exchange for an equal number of sodium ions (Knight) Isoptera 22:03, 11 December 2006 (UTC) = Isoptera. This can cause a major problem with the [hyperkalemia] of [metabolic shock] from surgery. ```` = Isoptera
These normal endogenous functions are the basis for the physiological consequences of chronic stress - prolonged cortisol secretion causes muscle wastage, hyperglycemia, and suppresses immune / inflammatory responses. The same consequences arise from long-term use of glucocorticoid drugs.
Also, long-term exposure to cortisol results in damage to cells in the hippocampus. This damage results in impaired learning. However, short-term exposure of cortisol helps to create memories; this is the proposed mechanism for storage of flash bulb memories.
Most serum cortisol, all but about 4%, is bound to proteins including corticosteroid binding globulin (CBG), and albumin. Only free cortisol is available to most receptors.
| Plasma Cortisol | Plasma ACTH | |
|---|---|---|
| Primary Hypercortisolism | ↑ | ↓ |
| Secondary Hypercortisolism ( pituitary, Cushing Disease ) | ↑ | ↑ |
| Primary Hypocortisolism ( Addison Disease ) | ↓ | ↑ |
| Secondary Hypocortisolism ( pituitary ) | ↓ | ↓ |
[edit] Pharmacology
As an oral or injectable drug, cortisol is also known as hydrocortisone. It is used as an immunosuppressive drug, given by injection in the treatment of severe allergic reactions such as anaphylaxis and angioedema, in place of prednisolone in patients who need steroid treatment but cannot take oral medication, and peri-operatively in patients on long-term steroid treatment to prevent an Addisonian crisis.
It is given by topical application for its anti-inflammatory effect in allergic rashes, eczema and certain other inflammatory conditions. Brand names include Aveeno(R), Emocort®, Epifoam®, Sigmacort®, Hyderm®, NovoHydrocort® Cortoderm®, Cortizone-10®, Cortaid®, and Lanacort®
It may also be injected into inflamed joints resulting from diseases such as gout.
Compared to prednisolone, hydrocortisone is about 1/4th the strength. Dexamethasone is about 40 times stronger than hydrocortisone. For side effects, see corticosteroid and prednisolone.
[edit] Diseases
- Hypercortisolism: Excessive levels of cortisol in the blood result in Cushing's syndrome.
- Hypocortisolism, or adrenal insufficiency: If on the other hand the adrenal glands do not produce sufficient amounts of cortisol, Addison's disease is the consequence.
[edit] See also
- Central serous retinopathy
- CortiSlim
- Cortitrol, supplement which claims to reduce cortisol.
- Cushing's syndrome
- HPA axis
- Hypopituitarism
- Post-traumatic stress disorder
- Relacore pill which claims to reduce Cortisol.
[edit] References
[edit] Online
- Hydrocortisone Fact Sheet
- "Relax, or you might become infertile!".
[edit] Printed
- Freeman, Scott (2002). Biological Science. Prentice Hall; 2nd Pkg edition (December 30, 2004). ISBN 0-13-218746-9.
- A. C. Guyton, J. E. Hall. Textbook of Medical Physiology. W.B. Saunders Company; 10th edition (August 15, 2000). ISBN 0-7216-8677-X.
- Knight, R.P., Jr. Kornfield, D.S. Glaser, G.H. Bondy, P.K. "Effects of Intravenous Hydrocortisone on Electrolytes in Serum and Urine in Man." Journal of Clinical Endocrinology 15: 176, 1955. ```` = Isoptera
- Palacios, R., Sugawara, I. "Hydrocortisone Abrogates Proliferation of T-Cells in Autologous Mixed Lymphocyte Reaction by Rendering the Interleukin-2 Producer Cells Unresponsive to Interleukin-1 and unable to synthesize the T-Cell Growth Factor." Scandinavian Journal of Immunology 15: 25, 1982. ```` = Isoptera
| Hormones and endocrine glands - edit |
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Hypothalamus: - TRH - CRH - GnRH - GHRH - somatostatin - dopamine | Posterior pituitary: vasopressin - oxytocin - lipotropin | Anterior pituitary: GH - ACTH - TSH - LH - FSH - prolactin - MSH - endorphins - lipotropin Thyroid: T3 and T4 - calcitonin | Parathyroid: PTH | Adrenal medulla: epinephrine - norepinephrine | Adrenal cortex: aldosterone - cortisol - DHEA | Pancreas: glucagon- insulin - somatostatin | Ovary: estradiol - progesterone - inhibin - activin | Testis: testosterone - AMH - inhibin | Pineal gland: melatonin | Kidney: renin - EPO - calcitriol - prostaglandin | Heart atrium: ANP Stomach: gastrin | Duodenum: CCK - GIP - secretin - motilin - VIP | Ileum: enteroglucagon | Liver: IGF-1 Placenta: hCG - HPL - estrogen - progesterone |
