Catecholamines: Definition, Structure, Function, High Levels, Normal Levels, Associated Symptoms and Blood Tests

It is a general term for the hormones dopamine, norepinephrine, and epinephrine, which occur naturally in the body.

Your body produces more catecholamines during times of stress. These hormones prepare your body for stress by making your heart beat faster and raising your blood pressure.

Catecholamine is secreted in the urine after it is broken down.

Structure

They are composed of two hydroxyl groups, an intermediate ethyl chain and a terminal amino group. The phenylethanolamines such as norepinephrine have a hydroxyl group at the chain acetate.

Function

They play a vital role in the metabolism of nutrients and the generation of body heat.

Some typical effects are increased heart rate, blood pressure, blood glucose levels, and a general sympathetic nervous system reaction.

They stimulate the consumption of oxygen and the consumption of fuels, such as glucose and free fatty acids, which generates heat.

 

They stimulate glycogenolysis and the breakdown of triglycerides, the stored form of fat, into free fatty acids.

They also have a role in regulating the secretion of multiple hormones.

High levels of catecholamines

High levels of catecholamine in the blood are associated with stress, which can be induced by psychological or environmental factors, such as high sound levels, bright light, or low blood sugar levels.

Extremely high catecholamine levels can also be caused by neuroendocrine tumors in the adrenal medulla, a treatable condition known as pheochromocytoma.

Some drugs, like tolcapone, raise the levels of all catecholamines.

Normal catecholamine levels

The primary catecholamines are broken down in the following ways before they are excreted in the urine:

  • Dopamine turns into homovanillic acid.
  • Epinephrine is converted to metanephrine and vanillylmandelic acid (VMA).
  • Norepinephrine is converted to normetanephrine and VMA.

What symptoms can cause my doctor to order a catecholamine blood test?

Your doctor likely ordered a catecholamine blood test because he is concerned that you may have a pheochromocytoma.

This tumor grows in your adrenal gland, where catecholamines are released. Most pheochromocytomas are benign, but it is essential to remove them, so they do not interfere with normal adrenal function.

Symptoms of pheochromocytoma

Symptoms of pheochromocytoma or adrenal tumor are:

  • High blood pressure
  • Fast heartbeat
  • An unusually hard heartbeat.
  • Intense sweating
  • Severe headaches come and go for an extended period.
  • Pale skin.
  • Unexplained weight loss
  • Feeling unusually scared for no reason.
  • Unexplained anxiety

Neuroblastoma symptoms

The symptoms of neuroblastoma are:

  • Pieces of tissue without pain under the skin.
  • Abdominal pain.
  • Chest pain.
  • Back pain.
  • Bone-ache.
  • Swelling of the legs
  • Wheezing
  • High blood pressure
  • Fast heartbeat
  • Diarrhea.
  • Bulging eyeballs.
  • Dark areas around the eyes.
  • Changes in the shape or size of the eyes, including changes in the size of the pupil.
  • Fever.
  • Unexplained weight loss

What is the purpose of the catecholamine blood test?

The catecholamine blood test measures the number of catecholamines in your body.

Doctors generally order the test to detect adrenal tumors in adults. These are tumors that affect the adrenal gland, located in the upper part of the kidney.

The test also checks for neuroblastomas, cancer that begins in the sympathetic nervous system, in children.