WATSON, S. J., H. AKIL AND J. M. WALKER. Anatomical and biochemical studies of the opioid peptides and related substances in the brain. PEPTIDES l: Suppl. 1, 11-20, 1980.--It is now clear that there are at least four opioid peptideneuronal systems in mammalian brain: the enkephalins, beta-endorphin and dynorphin. The focus of this presentation will be twofold--to focus on the multiple transmitt...

Reduction in the activity of the a-melanocyte-stimulating hormone (a-MSH) system causes obesity, and infusions of a-MSH can produce satiety, raising the possibility that a-MSH may mediate physiological satiety signals. Since a-MSH is coded for by the pro-opiomelanocortin (POMC) gene, we examined if POMC gene expression would be inhibited by fasting in normal mice or in models of obesity charact...

Autophagy degrades cytoplasmic contents to achieve cellular homeostasis. We show that selective loss of autophagy in hypothalamic proopiomelanocortin (POMC) neurons decreases α-melanocyte-stimulating hormone (MSH) levels, promoting adiposity, impairing lipolysis and altering glucose homeostasis. Ageing reduces hypothalamic autophagy and α-MSH levels, and aged-mice phenocopy, the adiposity and l...

The present study was designed to investigate the effect of α-melanocyte-stimulating hormone (α-MSH), nitric oxide (NO) and L-cysteine on melanin production and expression of related genes MC1R, Tyr, Tyrp-1 and Tyrp-2 in muzzle melanocytes of differently colored three native Hanwoo cattle. Muzzle samples were taken from black, brindle and brown Hanwoo and purified melanocytes were cultured with...

In this immunocytochemical study, we used light and electron microscopic observations in combination with morphometry to analyze the processing of pro-opiomelanocortin (POMC) in melanotrope cells of the intermediate pituitary of Xenopus laevis adapted to either a white or a black background. An antiserum was raised against a synthetic peptide including the cleavage site between ACTH and beta-li...

Mycothiol (MSH), a functional analogue of glutathione (GSH) that is found exclusively in actinomycetes, reacts with electrophiles and toxins to form MSH-toxin conjugates. Mycothiol S-conjugate amidase (Mca) then catalyzes the hydrolysis of an amide bond in the S conjugates, producing a mercapturic acid of the toxin, which is excreted from the bacterium, and glucosaminyl inositol, which is recyc...

A hallmark of sun exposure is increased melanin synthesis by cutaneous melanocytes which protects against photodamage and photocarcinogenesis. Irradiation of human keratinocytes or melanocytes with ultraviolet (UV) rays stimulates the synthesis and release of alpha-melanotropin (alpha-MSH) and adrenocorticotropic hormone (ACTH), which induce cyclic AMP (cAMP) formation and increase the prolifer...

Peptides of the pro-opiocortin class produce pronounced cardiovascular and natriuretic actions. We have investigated the acute cardiovascular effects of one of the most potent members of this class, y2-melanocyte stimulating hormone (y2-MSH), in rats. Pressor actions of y2MSH administered systemicaMy were eliminated by ganglionic blockade with chlorisondamine. Peripheral cholinergic blockade fa...

Alpha-melanocyte-stimulating hormone (α-MSH) is a protein with known capacity for protection against cardiovascular ischemia-reperfusion (I/R) injury. This investigation evaluates the capacity of α-MSH to mitigate I/R effects in an isolated working rat heart model and determine the dependency of these alterations on the activity of heme oxygenase-1 (HO-1, hsp-32), a heat shock protein that func...

The release of melanophore stimulating hormone (MSH) from the pars intermedia of the amphibian Xenopus laevis is regulated by multiple factors of hypothalamic origin. The aim of this study was to determine if potential secretagogues function through a direct action on the melanotrope cell. For this purpose an in vitro superfusion system containing isolated melanotropes (cell suspension) was uti...