Adrenocorticotropin, stimulation

Haksar, A., Maudsley, D. V., Kimmel, G. L., Peron, F. G., Robidoux, W. R., Jr., and Gahnon, G., 1974, Adrenocorticotropin stimulation of cyclic adenosine 3 -5 -mono-phosphate formation in isolated rat adrenal cells. The role of membrane sialic acid, Biochim. Biophys. Acta 362 356. 

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. 

Table 37-3 Diagnostic Uses of Thyroid-Stimulating Hormone and Adrenocorticotropin.

Matsumoto H, Maruyama M, Noguchi J, Horikoshi Y, Fujiwara K, Kitada C, Hinuma S, Onda H, Nishimura O, Inoue K, Fujino M. Stimulation of corticotropinreleasing hormone-mediated adrenocorticotropin secretion by central administration of prolactin-releasing peptide in rats. Neurosci Lett 2000 285 234—238. 

Anterior pituitary hormones include growth hormone (GH), thyrotropin (TSH), follicle-stimulating hormone (FSH), luteinizing hormone (LH), prolactin (PRL), and adrenocorticotropin (ACTH). Another peptide, B-lipotropin (B-LPH), is derived from the same prohormone, proopiomelanocortin, as ACTH. B-LPH is secreted from the pituitary (along with ACTH), and is a precursor of the opioid peptide B-endorphin (see Chapter 31 Opioid Analgesics Antagonists). 

Adrenocorticotropin is a peptide hormone produced in the anterior pituitary. Its primary endocrine function is to stimulate synthesis and release of cortisol by the adrenal cortex. Corticotropin can be used therapeutically, but a synthetic derivative is more commonly—and almost exclusively—used to assess adrenocortical responsiveness. A substandard adrenocortical response to exogenous corticotropin administration indicates adrenocortical insufficiency. 

Suggest which of the candidate pairs lead to the synthesis of the constituent hormone(s) (adrenocorticotropin, /Mipotropin, a-mclanocytc stimulating hormone, / -melanocyte stimulating hormone, and/or /i-cndorphin). 

Adrenocorticotropin (ACTH) a. AC stimulation G> fasciculata, glomeru-losa... 

The diencephalic DA neurons do not tonically regulate spontaneous (and perhaps rhythmic) activity of the HPA axis since pharmacological blockade of DA receptors has no effect on CRH mRNA expression in the paraventricular nucleus (Zhou et al., 2001), or secretion of adrenocorticotropin (Borowsky and Kuhn, 1992) or glucocorticoids into the circulation (Fuller and Snoddy, 1984). On the other hand, diencephalic DA neurons may participate in neuronal stimulation of the HPA axis since pharmacological activation of... 

Tilders FJH, Berkenbosch F, Smelik PG (1985) Control of secretion of peptides related to adrenocorticotropin, melanocyte-stimulating hormone and endorphin. In van Wimersma Greidanus TjB (Ed), Front Hormone Res Vol. 14, pp. 161-196. Karger, Basal. 

Exposure to pathobiological stressors causes the formation or release of mediators other than cytokines and ROS. These include stress-induced hormones and nitric oxide (NO). Stress responses stimulate the hypothalamic-pituitary axis causing the release of adrenocorticotropin, thereby elevating glucocorticoid levels. Glucocorti-... 

The paraventricular nucleus of the hypothalamus releases corticotrophin-releasing hormone, which stimulates the pituitary gland to release adrenocorticotropin (ACTH). ACTH travels via the blood to the adrenal gland, where it stimulates the release of cortisol. Cortisol is secreted by the cortex of the adrenal gland from a region called the zona fasciculata in response to ACTH. Elevated levels of cortisol exert negative feedback on the pituitary, which decreases the amount of ACTH released from the pituitary gland. 

Rafaeli et ai. have recently reported the existence of an adrenocorticotropin (ACTH)-like material in locust CC (5.) detectable by immunoassay. They also reported that ACTH at 10 mM stimulated liquid excretion from, and elevated levels of cAMP in, locust Malpighian tubules. Extracts of CC produced similar effects in the traditional in vitro assay (fi.). They believe that a diuretic peptide in locusts has at least immunological similarity to ACTH. While the partial sequence reported (4.) by Morgan et ai. has no apparent similarity to ACTH, it is conceivable that these groups could be investigating the same factor. 

Peptide neurotransmitters and hormones are collectively termed neuropeptides. Neuropeptides typically consist of small peptides of approximately 3 0 residues. Several neuropeptides and several of their regulatory functions are listed these neuropeptides and others function in multiple roles as physiological regulators (too numerous to hst in this short table). Ahhreviations are adrenocorticotropin hormone (ACTH), a-melanoc)de stimulating hormone (a-MSH), neuropeptide Y (NPY), and pituitary adenylate cyclase-activating peptide (PACAP). 

Adrenocorticotropin (ACTH) Melanocortin 2 receptor 39-residue peptide Stimulate the cortex of adrenal gland Solid-phase A -Boc chemistry... 

Pentagastrin is a short peptide that stimulates the production of gastric acid from the stomach by a direct action on gastrin receptors and of calcitonin from thyroid C cells (1). It also acts on cholecystokinin receptors centrally and stimulates the release of adrenocorticotropin (ACTH) and hence the production of glucocorticoids (2). 

Corticotropin is a peptide hormone secreted by the adenohypophysis, one of the derivatives of pro-opiomelanocortin (POMC) it acts primarily on the adrenal cortex, stimulating its grovrth and the secretion of corticosteroids. Its production is increased during times of stress. It is also known as adrenocorticotropic hormone, ACTH, corticotrophin, adrenocorticotrophin, and adrenocorticotropin. 

The adrenal gland produces cortisol in response to intermediate hormones, called adrenocorticotropin hormone (ACTH) and corticotropin-releasing hormone (CRH) via the humoral stress pathway, which extends from the brain to the adrenals (Figure 50-2). Once the body has received an environmental stress signal, it is detected by neurons in the cerebral cortex and transmitted to the hypothalamus. The hypothalamus then releases CRH via the classic secretory pathway into the anterior pituitary. CRH stimulates release of... 

C15. Colle, E., Ulstrom, R. A., Burley, J., and Gunville, R., Adrenocortical steroid metabolism in newborn infants. III. Urinary excretion of 17-Hydroxycorti-oosteroids following major surgery and stimulation with adrenocorticotropin. J. Clin. Endocrinol. Metab. 20, 1215-1224 (1960). 

ACTH, adrenocorticotropin a-su, alpha subunit -end, beta-endorphin p-FSH, beta follicle stimulating hormone fS-LH, beta luteinizing hormone -LPH, beta lipotropin -TSH, beta thyroid stimulating hormone, ER, estrogen receptor GH, growth hormone. 

Hormones themselves may be proteins. Notable examples are the more well-known insulin and the lesser-known thyrotropin and somatotropin (the growth hormone), as well as the ovarian luteinizing hormone and the follicle-stimulating hormone. If of relatively low molecular weight, protein-type hormones are also known as peptides, or specifically as peptide hormones. Examples listed, as a matter of course, are adrenocorticotropin, antidiuretic hormone, glucagon, and calcitonin. (Generally speaking, a peptide is a molecule with fewer than 50 amino acids, and a protein has more than 50 amino adds. The acids are combined in myriad combinations or permutations.)... 

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