What is Corticotropin, ACTH?
P-Corticotropin, also called ACTH, is a hormone secreted from the pituitary gland that controls the production and release of cortisol from the body's adrenal glands.
A well-controlled balance of ACTH is essential for maintaining homeostasis in the body, the ability to maintain a stable and balanced internal environment, despite external influences and changes. Imbalances can lead to serious endocrine diseases and affect well-being. Measurement of P-Corticotropin provides insight into the body's ability to handle stress, inflammation and hormonal regulation.
ACTH, function and regulation
ACTH acts as the conductor of the body's response to stress and regulates the production of cortisol, the "stress hormone" that affects metabolism, the immune system and the response to inflammation. When the body experiences stress or low levels of cortisol, ACTH stimulates the adrenal glands to produce and release this important hormone.
Why is P-Corticotropin analyzed?
P-Corticotropin analysis can be crucial in evaluating the health of the endocrine system and adrenal glands. Corticotropin is used to diagnose or monitor diseases related to the adrenal glands, such as Addison's disease and Cushing's syndrome. In addition, the measurement of ACTH can help identify causes of imbalances in cortisol production.
What can a high value of ACTH be due to?
An elevated value of ACTH, above >12 pmol/L can be due to several medical conditions and causes. Some possible explanations are presented below:
- Cushing's syndrome, a condition where the body produces too much cortisol. An overproduction from the pituitary gland can stimulate the adrenal glands to produce an excess of cortisol.
- Addison's disease, in some cases Addison's disease, where the adrenal glands produce too little cortisol, can lead to an increased production of ACTH as the body tries to compensate for low cortisol levels.
- Pituitary tumor, tumor in the pituitary gland can increase the production of ACTH, which in turn can lead to overproduction of cortisol
- Chronic renal failure, high levels of ACTH may occur in association with chronic renal failure.
What can a low value of ACTH be due to?
It is important to note that the diagnosis and interpretation of low ACTH levels should be made by a physician after an evaluation of the patient's medical history, symptoms, and other relevant tests. A low value can be due to several medical conditions and factors;
- Addison's disease, a cause of low ACTH levels, the adrenal glands are unable to produce enough cortisol, which is an important hormone for the body's stress response and fluid balance. The low ACTH value is a consequence of the impaired feedback loop, where normally low levels of cortisol would trigger an increased production of ACTH to stimulate the adrenal glands to produce more cortisol. In Addison's disease, this regulatory mechanism is disrupted, resulting in low levels of both cortisol and ACTH.
- Treatment with corticosteroids, when using synthetic corticosteroids (various drugs) can lower ACTH levels by providing negative feedback on natural production.
- Hypothalamus or pituitary insufficiency, injuries or diseases affecting the hypothalamus or pituitary gland can lead to a reduced production of ACTH.
Reference values for P-Corticotropin
The normal reference values for P-Corticotropin vary between laboratories but are usually within the range of 1.6-14 pmol/L. It is important to note that reference values may vary depending on the patient's age, gender and time of day when the test is taken.