View clinical trials related to ACTH.Filter by:
ACTH is a peptide secreted by pituitary gland and plays an important role in regulating cortisol secretion. ACTH is determined in plasma by immunoassays using specific antibodies. Its determination is difficult because of instability in whole blood. Several factors which influence ACTH stability in blood before analysis have been identified: temperature, hemolysis, time to centrifugation and presence of protease inhibitors. Published results on ACTH whole blood stability seem contradictory. The objective of this study is to evaluate the effect of aprotinin in 10 healthy volunteers. ACTH measurements will be performed on cobas e602 (Roche Diagnostics, Mannheim, Germany).
Between 10% and 15% of patients with endogenous hypercortisolism (Cushing syndrome) have ectopic (non-pituitary) production of adrenocorticotropin hormone (ACTH) that causes cortisol excess. In approximately 50% of these patients, the tumoral source of ACTH cannot be found initially despite very detailed and extensive imaging, including studies such as computed tomography, magnetic resonance imaging, and octreotide scan (Octreoscan) using the standard dose of indium-111 pentetreotide ([(111)In-DTPA-D-Phe]-pentetreotide). The sensitivity and specificity of structurally based imaging studies depends on anatomic alterations and the size of the tumor. In contrast, positron emission tomography (PET) and somatostatin ligand (like octreotide) imaging detect pathologic tissue based on physiologic and biochemical processes within the abnormal tissue. This protocol tests the ability of [(18)F]-L-3,4-dihydroxyphenylalanine ((18)F-DOPA) PET, Octreoscan and another somatostatin imaging analogue, (68)Ga-DOTATATE-PET, to localize the source of ectopic ACTH production. The study also examines whether administration of the glucocorticoid antagonist mifepristone can improve the sensitivity of the (68)Ga-DOTATATE PET/CT.
This study proposes to examine multiple aspects of the hypothalamic-pituitary-adrenal axis in younger endurance trained and sedentary men, and in older sedentary men.