The hypothalamic-pituitary-adrenal (HPA) axis is a vital body system.
The parts of the HPA axis include the hypothalamus, the pituitary gland, and the adrenal glands.
The HPA axis is connected to thecentral nervous systemand theendocrine system.
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Together they work to adjust the balance of hormones in the body and affect the stress response.
Hormones play an important role in the HPA axis.
Hormones are chemicals in the body that act like messengers.
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They give various body systems orders to start or stop different functions.
The hypothalamus is a small structure in the brain.
The hypothalamus is important in regulating hormone levels in the body.
The pituitary gland is about the size of a pea and is located at the base of the brain.
Its role is to create and release hormones in the body.
Hormones are vital in many body functions, including those that affect growth and maturation.
They are responsible for producing several types of hormones, including cortisol, aldosterone, adrenaline, and noradrenaline.
It sets off a series of events in the body in response.
Stress can mean not only emotional stress but also being scared or nervous.
The HPA axis gets the message and goes to work in seconds.
The hypothalamus then releases corticotropin-releasing hormone.
In addition to those physical changes, corticotropin-releasing hormone also affects the pituitary gland.
It tells the pituitary gland to start releasing adrenocorticotropic hormone.
The adrenocorticotropic hormone is released into the bloodstream.
Through the blood, it makes its way to the adrenal glands in the abdomen.
It binds to a spot on the adrenal glands.
The adrenal glands then get the message that they should start producingcortisoland other substances.
Function
The result of the activation of the HPA axis is the release of cortisol.
Cortisol is a steroidal hormone.
It has many effects and is sometimes called the stress hormone.
Cortisol must be balanced in the body: too much or too little can have wide-ranging health effects.
Cortisol has many properties that help a body respond to a stressful event.
It sends more blood to muscles, increases the amount ofglucosein the blood, and increasesblood pressure.
These are all helpful responses during a stressful event that might be a fight or flight situation.
Cortisol also turns off or dials down those body functions that wont help in a stressful situation.
There is another part to the HPA axis, called thenegative feedback loop.
Cortisol isn’t supposed to be produced for long periods of time.
Its production should end when the stressful event is over.
It connects with receptors on the hypothalamus.
This causes the HPA axis to slow down and stop the production of corticotropin-releasing and adrenocorticotropic hormones.
Significance
The activation of the HPA axis is an important body function.
However, when it is over activated, there could be health problems.
Associated Conditions
Your body needs to respond quickly to stress in our environment.
The stress response, which includes increased heart rate and extra energy, can help keep you safe.
While higher cortisol levels are needed at certain times, they can be harmful when elevated for too long.
This is because cortisol may suppress the immune system.
If that dampening continues, the person could be more susceptible to infections.
Higher levels of cortisol over long periods may also affect memory.
Chronic stress and the release of cortisol could cause problems with memory and attention.
Cortisol prepares the body for “fight or flight.”
But many people have chronic stress that may upset the balance this system is meant to maintain.
If you feel you need help, there are manystress management techniquesyou can employ.
A mental health professional may also be able to guide you to solutions.
National Institutes of Health.About adrenal gland disorders.
