Adrenocorticotropic hormone ACTH

In the anterior pituitary gland (see Hormones, anteriorpituitaryhormones), both adrenocorticotropic hormones (ACTH) and the endogenous opiate hormone, P-endorphin, are synthesized from a common prohormone (2) (see Opioids,endogenous). In the adrenal medulla, five to seven copies of another opiate hormone, methionine—enkephalin (Met-enkephalin), and one copy of leucine—enkephalin (Leu-enkephalin) are synthesized from each precursor molecule (3). 

Pregnenolone is transported from the mitochondria to the ER, where a hydroxyl oxidation and migration of the double bond yield progesterone. Pregnenolone synthesis in the adrenal cortex is activated by adrenocorticotropic hormone (ACTH), a peptide of 39 amino acid residues secreted by the anterior pituitary gland. 

Drugs with unknown mechanism of action are gabapentin, bromides (but see above effects on GABAergic transmission) and adrenocorticotropic hormone (ACTH), which is used in infantile spasms. 

Adrenocorticotrope Hormone (ACTH) Gluco-mineralocorticoid Receptors... 

Proopiomelanocortin (POMC) is the precursor peptide of hormones and neuropeptides expressed in the pituitary and the hypothalamus (adrenocorticotropic hormone (ACTH), lipotropin, a-melanocyte-stimulating hormone (aMSH), yMSH, 3-endorphin, and others). The main clinical consequences of POMC deficiency are adrenal insufficiency (due to absence of ACTH), red hair pigmentation (due to absence of MSH) and severe early-onset obesity (due to the lack of aMSH). 

Otfier fiormones accelerate tfie release of free fatty acids from adipose tissue and raise tfie plasma free fatty acid concentration by increasing the rate of lipolysis of the triacylglycerol stores (Figure 25—8). These include epinephrine, norepinephrine, glucagon, adrenocorticotropic hormone (ACTH), a- and P-melanocyte-stimulat-ing hormones (MSH), thyroid-stimulating hormone (TSH), growth hormone (GH), and vasopressin. Many of these activate the hormone-sensitive hpase. For an optimal effect, most of these lipolytic processes require the presence of glucocorticoids and thyroid hormones. These hormones act in a facilitatory or permissive capacity with respect to other lipolytic endocrine factors. 

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. 

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. 

Stress-induced adrenal insufficiency complicates 9% to 24% of septic patients and is associated with increased mortality. Adrenal-insuffident patients are identified by a adrenocorticotropic hormone (ACTH) stimulation test. Patients are given 250 meg ACTH and a cortisol level is checked within 30 to 60 minutes. Responders are defined as a greater than 9-mcg/dL increase in cortisol and non-responders as a less than 9-mcg/dL increase in cortisol. Septic shock patients refractory to resuscitation and vasopressors, and with adrenal insufifidency (non-responders to the ACTH test) should be administered intravenous hydrocortisone 200 to 300 mg per day in three divided doses for 7 days.24,44... 

Activated partial thromboplatin time (aPTT) Adrenocorticotropic hormone (ACTH) Alanine aminotransferase (ALT, SGPT) Albumin... 

A trophic hormone acts on another endocrine gland to stimulate secretion of its hormone. For example, thyrotropin, or thyroid-stimulating hormone (TSH), stimulates the secretion of thyroid hormones. Adrenocorticotropin, or adrenocorticotropic hormone (ACTH), stimulates the adrenal cortex to secrete the hormone cortisol. Both trophic hormones are produced by the pituitary gland in fact, many trophic hormones are secreted by the pituitary. The pituitary gland is sometimes referred to as the "master gland" because its hormones regulate the activity of other endocrine glands. 

Thyroid-stimulating hormone (TSH) Adrenocorticotropic hormone (ACTH) Prolactin (PRL)... 

FIGURE 1 8-5 Tissue-specific processing of the pro-opiomelanocortin (POMC) precursor yields a wide array of bioactive peptide products. Processing of the POMC precursor varies in various tissues. In anterior pituitary, adrenocorticotropic hormone (ACTH (1-39)) and P-1 ipo tropin (P-LPH) are the primary products of post-translational processing. Arcuate neurons produce the potent opiate P-endorphin (P-endo (1-31)) as well as ACTIK1 -13) NIT,. Intermediate pituitary produces a-melanocyte-stimulating hormone (aMSH), acetylated P endof 1 31) and P-endo(l-27). NTS, nucleus tractus solitarius. 

Adrenocorticotropic hormone (ACTH) gel, 40 to 80 USP units, may be given intramuscularly every 6 to 8 hours for 2 to 3 days and then discontinued. Studies with ACTH are limited, and it should be reserved for patients with contraindications to first-line therapies (e.g., heart failure, chronic renal failure, history of GI bleeding). 

As would be expected of active protein secreting cells, glandular epithelial tissue, the cytokine secreting cells of the immune system and the blood vessel endothelium, have an extensive internal structure consisting of rough endoplasmic reticulum and numerous mitochondria. Peptide hormones, growth factors and cytokines like all proteins are synthesized by DNA transcription and mRNA translation. The primary transcript of the mRNA may code for an inactive prohormone which requires careful proteolysis to produce the active hormone, as for example in the case of insulin. Adrenocorticotropic hormone (ACTH) is particularly interesting in this respect because... 

Anterior part produces its own hormones in response to hypothalamic releasing hormones, e.g., adrenocorticotropic hormone ACTH, luteinizing hormone LH, follicle-stimulating hormone FSH, prolactin, growth hormone, thyroid-stimulating hormone TSH Thyroid Regulation of metabolism, development, and maturation... 

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