What is the role of the hypothalamus-pituitary-adrenal (HPA) axis (grouping) in stress?

The HPA axis is a grouping of responses to stress by the brain and the pituitary and adrenal glands. First, the hypothalamus (a central part of the brain) releases a compound called corticotrophin releasing factor (CRF), which was discovered in 1981. The CRF then travels to the pituitary gland, where it triggers the release of a hormone, adrenocorticotrophic hormone (ACTH). ACTH is released into the bloodstream and causes the cortex of the adrenal gland to release the stress hormones, particularly cortisol, which is a corticosteroid hormone. Cortisol increases the availability of the body's fuel supply (carbohydrate, fat, and glucose), which is needed to respond to stress. However, if cortisol levels remain elevated for too long, then muscle breaks down, there is a decreased inflammatory response, and suppression of the immune (defense) system occurs.

Because they suppress the immune system, corticosteroids in measured doses are used to treat many illnesses that are characterized by inflammation or an overactive immune system, such as asthma and inflammatory bowel disease. For the same reason, they are used to help reduce the chances that our body will immunologically reject a transplanted organ. Corticosteroids also can cause fluid retention and high blood pressure. Therefore, it is critical that the response to corticosteroids be carefully controlled (modulated). This control usually is accomplished by a feedback mechanism in which increased cortisol levels feeding back to the hypothalamus and pituitary turn off production of ACTH. In addition, extremely high levels of cortisol can cause mental changes, including depression and psychosis, which disappear when the levels return to normal.

(click title link to learn more...only works from blog post)

Got Butterflies? Find out Why. Your Life. BAM Body and Mind.

What is Short-Term Stress?

Have you ever started a new school, argued with your best friend, or moved? Do you have to deal with the ups and downs of daily life — like homework or your parents’ expectations? Then you already know about stress. In fact, everyone experiences stress. Your body is pre-wired to deal with it — whether it is expected or not. This response is known as the stress response, or fight or flight.

The fight or flight response is as old as the hills. In fact, when people used to have to fight off wild animals to survive, fight or flight is what helped them do it. Today, different things cause stress (when was the last time you had to fend off a grizzly bear?), but we still go through fight or flight. It prepares us for quick action — which is why the feeling goes away once whatever was stressing you out passes! It can also happen when something major happens — like if you change schools or have a death in your family.

Everyone has weird feelings when they are stressed. Fight or flight can cause things like sweaty palms or a dry mouth when you are nervous, or knots in your stomach after an argument with someone. This is totally normal and means that your body is working exactly like it should. There are lots of signs of stress — common types are physical (butterflies in your stomach), emotional (feeling sad or worried), behavioral (you don’t feel like doing things), and mental (you can’t concentrate). Most physical signs of stress usually don’t last that long and can help you perform better, if you manage them right.

So, when you feel stress, what happens to make your body do the things it does? According to the experts, three glands “go into gear” and work together to help you cope with change or a stressful situation. Two are in your brain and are called the hypothalamus (hipe-o-thal-a-mus) and the pituitary (pi-to-i-tary) gland. The third, the adrenal (a-dree-nal) glands, are on top of your kidneys. The hypothalamus signals your pituitary gland that it is time to tell your adrenal glands to release the stress hormones called epinephrine (ep-in-efrin), norepinenphrine (nor-ep-in-efrin), and cortisol (cor-ti-sol). (To Read More Click Title Link To This Post)