metyrapone(redirected from mepyrapone)
a synthetic compound that selectively inhibits an enzyme responsible for the biosynthesis of corticosteroids; it is used as a diagnostic aid in a test of pituitary reserve.
An inhibitor of adrenocortical steroid C-11 β-hydroxylation, administered orally or intravenously to determine the ability of the pituitary gland to increase its secretion of corticotropin; because 11-deoxycorticosteroids, as a consequence of metyrapone administration, only weakly inhibit pituitary corticotropin secretion, the normal pituitary gland will appreciably increase its output of this hormone.
metyrapone/me·tyr·a·pone/ (mĕ-tēr´ah-pōn) a synthetic compound that selectively inhibits an enzyme responsible for the biosynthesis of corticosteroids; it is used as a diagnostic aid for determination of hypothalamicopituitary-adrenocortical reserve.
a diagnostic test drug.
indications It is used to test hypothalamic and pituitary function.
contraindications Adrenocortical insufficiency or hypersensitivity prohibits its use.
adverse effects Among the most serious adverse effects are nausea, dizziness, and allergic rash.
metyraponeAn agent used to evaluate the hypothalamus-pituitary-adrenal axis, especially abnormal pituitary activity. Metyrapone inhibits 11-beta-hydroxylase, the final enzyme in cortisol synthesis. The inhibition results in accumulation of 11-deoxycortisol in the adrenal cortex, resulting in decreased negative feedback of ACTH synthesis by the pituitary; it therefore also results in increased ACTH and increased 11-deoxycortisol, as well as its metabolite, tetrahydrocortisol, which is measured in the urine as so-called Porter-Silber compounds.
metyraponeA diagnostic tool for evaluating the hypothalamus-pituitary-adrenal 'axis', especially, abnormal pituitary activity
metyraponeAn ALDOSTERONE inhibitor drug used to treat aldosterone-induced OEDEMA and CUSHING'S syndrome. A brand name is Metopirone.
a compound that selectively inhibits adrenocortical 11β-dehydroxylase and the synthesis of cortisol.
blood levels of cortisol and 11-desoxycortisol are measured, before and after administration of metapyrone. In pituitary dependent hyperadrenocorticism, there is a decrease in cortisol and increase in 11-desoxycortisol; both values decrease if there is an adrenal tumor.