A-Melanocyte-stimulating hormone

CART (cocaine- and amphetamine-regulated transcript) is a hypothalamic peptide that inhibits both normal and starvation-induced feeding when injected into cerebral ventricles of rats. CART is co-localized with the anorexigenic peptide a-melanocyte-stimulating hormone in neurons of the arcuate nucleus. Secretion of CART is stimulated by leptin and CART may be an endogenous inhibitor of food intake. 

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). 

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. 

Grabbe, S. et al., a-Melanocyte-stimulating hormone induces hapten-specific tolerance in mice, J. Immunol. 156, 473 178, 1996. 

Alpha LFW-1 ring/block test, 9 714 (H)-a-lipoic acid, 17 672 a-melanocyte-stimulating hormone... 

Stouffer, J. E., and /. A, Watters jr. The reversible masking of the lysine residue in a-melanocyte stimulating hormone. Biochim. Biophys. Acta 104. 214 -217 (1965). 

The anorexigenic (appetite-suppressing) neurons in the arcuate nucleus produce a-melanocyte-stimulating hormone (a-MSH), formed from its polypeptide precursor pro-opiomelanocortin (POMC Fig. 23-6). Release of a-MSH causes the next neuron in the circuit to send the signal to the brain, Stop eating ... 

DBS, CTS, NLS and CRS stand for DNA binding signal, cytosolic translocation signal, nuclear localization signal and cell recognition signal, respectively. MSH is a-melanocyte stimulating hormone. pLK is poly lysine. 

Only a small number of proteins and peptides have been analyzed by various investigators by methods designed specifically to determine whether methionine sulfoxide is one of the constituent amino acids. One of these, an analog of the a-melanocyte-stimulating hormone from bovine pituitary glands (9), was found to contain the sulfoxide. However, the authors expressed some concern over the possibility of oxidation during isolation of the sample. 

Goudreau JL, Manzanares J, Lookingland KJ, Moore KE (1993) 5HT2 receptors mediate the effects of stress on the activity of periventricular hypophysial dopaminergic neurons and the secretion of a-melanocyte-stimulating hormone. J Pharmacol Exp Ther 265 303-307. 

Mezey E, Kiss JZ, Mueller GP, Eskay R, O Donohue TL, Palkovits M (1985) Distribution of the pro-opiomelanocortin derived peptides, adrenocorticotrope hormone, a-melanocyte-stimulating hormone and P-endorphin (ACTH, a-MSH, P-END) in the rat hypothalamus. Brain Res 525 341-347. 

Pan Y-T, Tian Y, Lookingland KJ, Moore KE (1992) Neurotensin-induced activation of hypothalamic dopaminergic neurons is accompanied by a decrease in pituitary secretion of prolactin and a-melanocyte-stimulating hormone. Life Sci 50 2011-2017. 

Penny RJ, Thody AJ (1978) An improved radioimmunoassay for a-melanocyte-stimulating hormone (a-MSH) in the rat serum and pituitary a-MSH levels after drugs which modify catecholamine neurotransmission. 

Vecsernyes M, Krempels K, Toth BE, Julesz J, Makara GB, Nagy GM (1997) Effect of posterior pituitary denervation (PPD) on prolactin (PRL) and a-melanocyte-stimulating hormone (aMSH) secretion of lactating rats. Brain Res Bull 43 313-319. 

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