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The Adrenal Glands

An informative article on: The Adrenal Glands.

There are two tiny organs that rest just above the kidneys on either side of the body. These tiny glands actually play an extremely crucial part in producing several hormones that have an impact on development and growth, how we handle stress and they also assist in the regulation of kidney function. We are referring to the adrenal glands which actually have two distinct sections, each having a distinct function.

Composition and Function of the Adrenal Glands

There are actually two separate organs in each adrenal gland. The portion on the outside is called the adrenal cortex while the inside is the adrenal medulla. Both portions secrete hormones and the main difference is that the adrenal medulla does not secrete hormones that are essential for life while the adrenal cortex does. For example, those hormones necessary for growth and development would be secreted by the adrenal cortex while the hormones related to how we handle emotional stress would come from the adrenal medulla.

The Adrenal Cortex

Common hormones that are produced by the adrenal cortex are glucocorticoids such as cortisol that aid in the control of blood sugar and in the metabolism of proteins and fats. Those hormones also trigger how we respond to physical stressors such as major illnesses, high fevers and injuries. On the other hand, there are mineralcorticoids like aldosterone that help to control the volume of blood as well as in the regulation of blood pressure by signaling the kidneys how much water and sodium to retain. Some important secondary sex hormones are also secreted from the adrenal cortex. These hormones determine some of the secondary sex characteristics in both males as well as females.

The Adrenal Medulla

There probably isn’t a person alive who hasn’t heard the term adrenaline referred to on an almost daily basis. It is one of the best known of hormones secreted by the adrenal glands but not, by far, the most important. Adrenaline is also referred to as epinephrine which raises the heart rate and also improves oxygen intake by opening the airways. Epinephrine is usually released when a person is scared and is what is commonly referred to as the ‘fight or flight’ response. Another hormone released by the adrenal medulla is norepinephrine but is actually associated more in terms of normal activity and not emergency reactions. High blood pressure is caused by an over abundance of norepinephrine.

Disorders of the Adrenal Cortex

The good news is that adrenal cancer is extremely rare in that it statistically strikes only one in every one million people. However, there are two other conditions, or disorders, that are more common to the adrenal cortex. When there is too much cortisol present it can result in Cushing’s syndrome while the absence of sufficient cortisol could result in Addison’s disease. It is held to be important to control the amount of physical stressors placed on the body in order to regulate the amount of cortisol being released. This, in turn, helps to prevent either of these disorders.

While the adrenal glands are tiny in size, they are not tiny in function. Some of the hormones they secrete are necessary to the development and maintenance of life while others control our response to everyday living, stressful situations and even determine some of our secondary sex characteristics. Other hormones help to determine body weight and metabolism. These are two small glands with a very big job.