Midnight One Piece Dexamethasone Inhibition Test

The midnight piece of dexamethasone inhibition test is performed by the following principle. Under normal circumstances, ACTH secretion by the pituitary is regulated by the level of cortisol in the blood circulation. Exogenous administration has a strong inhibitory effect on pituitary ACTH secretion, but its own dose is small, and it has little effect on blood and urine cortisol determination. Synthetic corticosteroid-dexamethasone, observe changes in blood and urine cortisol and plasma ACTH. It can reflect the function of ACTH secreted by pituitary and whether adrenal cortex function depends on ACTH. Can distinguish Cushing disease and Cushing syndrome.