Adrenocorticotropic hormone ACTH, corticotropin

Formation of these drugs is under the direct control of a polypeptide adrenocorticotropic hormone (ACTH, corticotropin), which is processed by the anterior lobe of the hypophysis. Human ACTH consists of 39 amino acids and has a molecular weight of about 4500. It differs from animal ACTH in the amino acid compositions at positions 29-33. 

The glucocorticoid cortisol is secreted from the adrenal cortex as a stress response under the control of adrenocorticotropic hormone (ACTH, corticotropin) produced by the anterior pituitary. Cortisol promotes catabolism by inducing synthesis of specific proteins. Cortisol binds to a cytosolic cortisol receptor which then translocates to the nucleus and switches on the expression of specific genes, notably that for PEP carboxykinase (PEPCK). Cortisol-induced expression of the key gluconeogenesis enzyme PEPCK increases levels of the enzyme and hence increases gluconeogenesis and available blood glucose. The cAMP-and cortisol-mediated pathways for induction of PEPCK expression are further linked by CREB-dependent expression of a coactivator protein PGC-1 that promotes cortisol-dependent expression of PEPCK. 

PRL), luteinizing hormone (LH), follicle-stimulating hormone (FSH), thyroid-stimulating hormone (TSH), adrenocorticotropic hormone (ACTH, corticotropin), and j6-endorphin. /6-Lipotrophic hormone (/1-LPH) is also secreted but serves mainly as a precursor of -endorphin and is not regarded as a hormone. In species that possess a prominent intermediate lobe, the pituitary also secretes a-and /i-melanocyte-stimulating hormones (MSH), which affect skin coloration. 

Adrenocorticotropic Hormone (ACTH) (Corticotropin) Anterior Pituitary (Corticotroph) 39 aa 2p25 Stimulates steroidogenesis in all three zones of the adrenal cortex, thereby increasing secretion of cortisol, DHEAS, and aldosterone. Stimulated by CRH and inhibited by cortisol. 

Adrenal corticosteroids, adrenocorticoids, corticosteroids, corticoids, cortins an important group of steroid hormones, formed in the adrenal cortex in response to adrenocorticotropic hormone [ACTH, Corticotropin (see)]. A.c. are structurally related to pregnane (see Steroids) they contain a carboxyl group with a neighboring a,p-unsaturated bond in ring A, a ketol side chain in position 17, and other oxygen functions, particularly in positions 11,17,21 and 18. 

Adrenal hormone production is controlled by the hypothalamus and pituitary gland. Corticotropin-releasing hormone (CRH) is secreted by the hypothalamus and stimulates secretion of adrenocorticotropic hormone (ACTH), also known as corticotropin from the anterior pituitary. ACTH, in turn, stimulates the adrenal cortex to produce cortisol. When sufficient or excessive cortisol levels are reached, a negative feedback is exerted on the secretion of CRH and ACTH, thereby decreasing overall cortisol production. The control of adrenal androgen synthesis also follows a similar negative-feedback mechanism. 

ACTH, adrenocorticotropic hormone or corticotropin FDA, Food and Drug Administration HPA, hypothalamic-pituitary-adrenal IV, intravenously. aThe 250 meg dose has also been administered intramuscularly in an outpatient setting. The 1 meg dose is not FDA-approved. 

ACTH, adrenocorticotropic hormone or corticotropin CRH, corticotropinreleasing hormone. 

ACTH, adrenocorticotropic hormone or corticotropin CRH, corticotropin-releasing hormone CT, computed tomography MRI, magnetic resonance imaging 0, none +, mild ++, moderate +++, pronounced. 

Corticotropin [adrenocorticotropic hormone (ACTH)] has been used for acute gouty flares. Worldwide supply problems and the possible superiority of traditional corticosteroids have resulted in decreased use. 

FIGURE 18-7 Processing of the proopiomelanocortin (POMC) precursor proceeds in an ordered, stepwise fashion. Cleavage of the POMC precursor occurs at seven sites, with some of the reactions being tissue-specific. The circled numbers indicate the temporal order of cleavage in tissues where these proteolytic events occur. ACTH, adrenocorticotropic hormone CLIP, corticotropin-like intermediate lobe peptide JP, joining peptide LPH, lipotropin MSH, melanocyte-stimulating hormone PC, prohormone convertase. 

Corticotropin-releasing factor (CRF) Adrenocorticotropic hormone (ACTH)... 

Note. ACTH = adrenocorticotropic hormone CRH = corticotropin-releasing hormone ... 

Corticotropin (adrenocorticotropic hormone, ACTH) regulates the function of the adrenal cortex and has numerous other effects on metabolism. It contains 39 amino acids in the form of a random coil, owing to the presence of several proline residues that prevent helix formation. Species differences are seen in amino acids 25-39 the rest of the ACTH molecule is identical in all animals and humans. The first 24 amino acids are responsible for all of the biological action of ACTH synthetic human ACTHj 24 is known as cosyntropin. 

FIGURE 29-2 Negative feedback control of glucocorticoid synthesis. Cortisol limits its own synthesis by inhibiting the release of corticotropin-releasing hormone [CRH] from the hypothalamus and adrenocorticotropic hormone [ACTH] from the anterior pituitary. 

Adrenocorticotropic hormone (ACTH) Polypeptide with 39 amino acids Corticotropin-releasing hormone (CRH) peptide with 41 amino acids Unknown Causes release of steroid hormones from adrenal cortex... 

Secretion and actions of adrenocorticotropic hormone (ACTH). CRH, corticotropin-releasing hormone. 

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