What is the Difference Between Catecholamines and Cortisol

The key difference between catecholamines and cortisol is that catecholamines are hormones synthesized in the adrenal medulla of the adrenal gland and inside some of the sympathetic nerve fibers, while cortisol is a hormone synthesized by the adrenal cortex of the adrenal gland.

Catecholamines and cortisol are chemical messengers in the human body. They are both involved in the human stress response. Catecholamines include epinephrine, norepinephrine, and dopamine. Catecholamines function as neurotransmitters and hormones in the body. Cortisol is a single chemical. Its main function is the regulation of metabolism and regulation of other hormones.

CONTENTS

1. Overview and Key Difference
2. What are Catecholamines 
3. What is Cortisol
4. Similarities – Catecholamines and Cortisol
5. Catecholamines vs Cortisol in Tabular Form
6. Summary – Catecholamines vs Cortisol

What are Catecholamines?

Catecholamines are hormones synthesized in the adrenal medulla of the adrenal gland and inside some of the sympathetic nerve fibers. They are monoamine neurotransmitters. They also function as hormones. Catecholamines are organic compounds that have a catechol group and an amine side chain. They can be free molecules or substituents of a larger molecule. Catecholamines are derived from tyrosine, which is usually derived from dietary sources, and from another amino acid called phenylalanine. Catecholamines are water soluble and are 50% bound to plasma proteins in the circulation. Catecholamines include epinephrine, norepinephrine, and dopamine. The release of the hormones epinephrine and norepinephrine from the adrenal medulla is part of the fight-or-flight response in humans.

Tyrosine is an amino acid created from phenylalanine by hydroxylation. The enzyme catalyzing this reaction is phenylalanine hydroxylase. Tyrosine can also be ingested from dietary protein. Later, catecholamines–secreting cells use several reactions to convert tyrosine to L-DOPA and then to dopamine. Ultimately, dopamine is further converted to norepinephrine and epinephrine, depending on the cell type. Furthermore, there are various stimulant drugs, such as substituted amphetamines, which are catecholamine analogs.

What is Cortisol?

Cortisol is a steroid hormone that belongs to the glucocorticoid class of hormones. Cortisol is also used as a medication. When it is used as a medication, it is called hydrocortisone. Many animals produce cortisol. It is mainly synthesized by the Zona fasciculata of the adrenal cortex in the adrenal gland. Some other tissues also produce cortisol in lower quantities.

Normally, cortisol is released with a diurnal cycle. Specifically, its release is increased in response to stress and low blood glucose concentration. The main function of cortisol is to increase blood sugar through gluconeogenesis. It also suppresses the immune system, regulates blood pressure, aids the metabolism of fat, protein, and carbohydrates, and helps control the sleep-wake cycle. Furthermore, cortisol also decreases bone formation. Cushing’s syndrome generally causes high levels of cortisol. On the other hand, primary adrenal insufficiency and secondary adrenal insufficiency cause low levels of cortisol.

What are the Similarities Between Catecholamines and Cortisol?

• Catecholamines and cortisol are two chemical messengers in the human body.
• They are involved in the human stress response.
• Both are chemicals produced by the adrenal gland.
• Both perform an extremely important function in the human body that help the survival of humans.
• Deregulation of both hormones causes diseases

What is the Difference Between Catecholamines and Cortisol?

Catecholamines are hormones synthesized in the adrenal medulla of the adrenal gland and inside some of the sympathetic nerve fibers, while cortisol is a hormone synthesized by the adrenal cortex of the adrenal gland. Thus, this is the key difference between catecholamines and cortisol. Moreover, catecholamines are responsible for the body’s fight or flight response, while cortisol increases blood sugar through gluconeogenesis, suppresses the immune system, regulates blood pressure, aids the metabolism of fats, proteins, and carbohydrates, helps control the sleep-wake cycle, and decreases bone formation.

The below infographic presents the differences between catecholamines and cortisol in tabular form for side-by-side comparison.

Summary – Catecholamines vs Cortisol

Catecholamines and cortisol are both important hormones in the human body. They are involved in the human stress response. Catecholamines are synthesized in the adrenal medulla of the adrenal gland and inside some of the sympathetic nerve fibers. Cortisol is synthesized by the adrenal cortex of the adrenal gland. So, this is the key difference between catecholamines and cortisol.

Reference:

1. “Catecholamines: What Are They, and How Do They Function?” Medical News Today, MediLexicon International.
2. “Cortisol: What It Is, Function, Symptoms & Levels.” Cleveland Clinic.

Image Courtesy:

1. “Catecholamines biosynthesis” By NEUROtiker – own work (CC BY-SA 3.0) via Commons Wikimedia
2. “Cortisol” By NEUROtiker – Own work (Public Domain) via Commons Wikimedia