Steroid hormone secreted in the adrenal cortex that targets adipose (fat), muscle tissue and the liver. Also known as hydrocortisone, cortisol is one of several glucocorticoids. It stimulates the transfer of amino acids from muscles to the liver and fatty acids from adipose cells to the liver. The fatty acids and amino acids released are used in gluconeogenesis (synthesis of glucose from sources besides carbohydrates).

Glucocorticoids also have anti-inflammatory action which has resulted in widespread clinical applications.

cortisol: in humans and other mammals the main glucocorticoid hormone produced by the adrenal cortices; also known as hydrocortisone. It is essential to the maintenance of life. It is available in synthetic form.

Dictionary of Sexology Project: Main Index

One of the survival hormones your body releases when under stress. Cortisol likes to break down muscle tissue which is a very Bad Thing. It's been shown that people with high stress lifestyles have above average levels of cortisol (which might help explain the numerous health problems associated with stress.) Another excellent way to release cortisol is to overtrain in the gym, applying stress to your body in excess of your ability to adapt to it.

C₂₁H₃₀O₅

Carbon, Hydrogen, Oxygen.

Carbon is coal and diamonds. Oxygen and Hydrogen is water. Carbon and Hydrogen and Oxygen together is cortisol.

Chemistry is cool.

Cortisol is a hormone that responds to stress. It raises blood pressure and blood sugar, suppresses the immune system, lowers bone formation, and creates memories in short-term exposure.

Cortisol is synthesized from progesterone in the cortex of the adrenal glands. Hydroxylation of several of the progesterone's carbon atoms in the zona fasciculata of the Adrenal cortex changes progesterone to cortisol. The adrenal glands manufacture a number of substances, including some sex hormones, but cortisol is their main secretion. Cortisol is derived from cortex — some dots I didn't have to connect for you.

While cortisol emerges from the adrenal proper, there are other structures involved in its production. Synthesis is stimulated by ACTH from the anterior lobe of the pituitary gland, which is bumped into motion by CRH released by the hypothalamus.

When it's made synthetically the result is what we call hydrocortisone — most famously, the very geriatric joint pain reliever.

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Flashbulb memories — it's like the name says: a memory created in a flash. We all have them. Many of us have nothing of our early youth except for flashbulb memories.

Short-term exposure to cortisol creates memories. Cortisol is said to be the mechanism of our flashbulb memories. I wake up clammy once a month or so remembering countless almost-deaths because of cortisol. Thanks, cortisol.

Many people think that cortisol is released to induce stress. Actually it's the opposite case. When someone encounters stress, cortisol is released to restore homeostasis. By promoting the breakdown of carbohydrates, proteins and lipids, it acts as an antagonist to insulin and mobilizes energy reserves. I suspect we'll need to read entire books to understand the subtleties there. Blood pressure rises; the immune system is suppressed. Inflammation is superceded by a rush of energy. Cortisol is why you feel good after getting your ass kicked.

Adrenaline junkies may be better called cortisol junkies. Cortisol's kind of a dorky-sounding hormone, though.

Of course, there's always too much of a good thing. Exposure to chronic stress may break down the normal ACTH trigger cycle described above. Abnormal exposure to cortisol in early childhood is linked with learning problems. Bone weakness leads to wasting muscle; immunosuppression to quell inflammation becomes a double-edged sword when infection rears its ugly head.

Too much cortisol can result in Cushing's syndrome; too little can cause Addison's disease.

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Cortisol can be administered orally, intravenously, or topically to counter inflammatory responses detrimental to health. It's injected into joints throbbing from gout and rubbed on rashed skin. It fights catastrophic allergic reactions, like anaphylaxis.

Testing cortisol levels in the blood can reveal problems with the adrenal glands or the pituitary gland or the presence of Cushing's or Addison's.

Cortisol test

Cortisol tests are done either by blood or urine.

Urine samples are collected over a 24-hour period. The period's first evacuation is discarded; subsequent evacuations are collected in a large container which holds about a gallon and already contains a small amount of preservative. Patients are encouraged to keep urine refrigerated during the collection period and keep the sample free of pubic hair, feces, menstrual blood, and so on. Because very little cortisol is present in the urine, this test is typically only used to detect Cushing's syndrome.

Blood collection is standard. If you've had bloodwork done you know every agonizing step. Rubber strap around the arm, prodding for veins, needle in, blood out, needle out, disturbingly more blood out, gauze over wound. Fainting optional. I don't like needles.

In urine, normal cortisol levels are less than 50 µg per 24-hour sample.

Because cortisol levels fluctuate throughout the day, in blood tests normal morning samples are rated at 5 to 25 µg/dL while normal afternoon comes in at 3 to 16 µg/dL.

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Sources

WebMD
www.webmd.com/hw/lab_tests/hw6227.asp

Wikipedia
en.wikipedia.org/wiki/cortisol

Weber, Charles. "The Purpose of Cortisol."
members.tripod.com/~charles_W/cortisol.htm

Medline Plus
www.nlm.nih.gov/medicineplus/ency/article/002582.htm