ACTH Stimulation Test
Alternate Names : Cortrosyn Stimulation Test, Tests of Adrenal Reserve
This test checks how the adrenal glands respond to a
certain hormone. The hormone is called adrenocorticotrophic hormone,
also known as ACTH. ACTH is made in the pituitary gland and travels
through the bloodstream to the adrenal glands. ACTH stimulates the
adrenal gland to release cortisol. Cortisol is a key factor in many functions
in the body's metabolism of fats,
carbohydrates,
sodium,
potassium,
and protein.
Who is a candidate for the test?
This test is ordered when the doctor suspects that a
person's adrenal gland is not working the way it should.
How is the test performed?
Cortisol levels in the bloodstream are measured before and
after an injection of ACTH into the blood or muscle. A blood sample
is taken from a vein on the forearm or hand. First, the skin over the vein
is cleaned with an antiseptic. Next, a strong rubber tube, called a tourniquet,
is wrapped around the upper arm. This enlarges the veins in the lower
arm by restricting blood flow through them. A fine needle is
inserted into a vein, and the tourniquet is removed. Blood flows from
the vein through the needle and is collected in a syringe or vial for testing
in the laboratory. After the needle is withdrawn, the puncture site is
covered for a short time to prevent bleeding.
|