Growth hormone secretagogue receptor secretagogue receptor is activated, a variety of different intracellular signaling cascades can result, depending on the cell type in which the receptor is expressed. These intracellular signaling cascades include mitogen-activated protein kinase (MAPK)), protein kinase A (PKA), protein kinase B (PKB), also known as AKT), and AMP Activated Protein Kinase (AMPK) cascades. It is well-characterized that activating the growth hormone secretagogue receptor with ghrelin induces an orexigenic state, or general feeling of hunger. However, ghrelin may also play a role in behavioral reinforcement. Studies in animal models, found that food intake increased when ghrelin was specifically administered to just the
Melanocyte-stimulating hormone Melanocyte-stimulating hormone The melanocyte-stimulating hormones, known collectively as MSH, also known as melanotropins or intermedins, are a family of peptide hormones and neuropeptides consisting of α-melanocyte-stimulating hormone (α-MSH), β-melanocyte-stimulating hormone (β-MSH), and γ-melanocyte-stimulating hormone (γ-MSH) that are produced by cells in the pars intermedia of the anterior lobe of the pituitary gland. Synthetic analogues of α-MSH, such as afamelanotide (melanotan I; Scenesse), melanotan II, and bremelanotide (PT-141), have been developed and researched. The various forms of MSH are generated from different cleavages of the proopiomelanocortin protein, which also yields other important neuropeptides like adrenocorticotropic hormone. Melanocytes in skin make and