Endogenous peptide signals

INDIRECT EVIDENCE FOR ENDOGENOUS PEPTIDE SIGNALS Receptor-like Protein Kinases... 

ATRIAL NATRIURETIC PEPTIDE RECEPTOR AGONISTS include ANP itself (also called atrial natriuretic factor (ANF), or atrlopeptin), a peptide made up of 28 amino acids and is contained in secretory granules in heart atrial cells. ANP is released in response to stretch in the atria, as occurs with increased central venous pressure, thus signalling volume overload in the circulation. The peptide has an effect on the kidney leading to increased Na and water excretion, vasodilation, increased vascular permeability and modified release of a number of other hormones and neurotransmitters. There are at least three related endogenous peptides ANP (atrial natriuretic peptide),... 

Fahnestock ML, Johnson JL, Feldman RM, Neveu JM, Lane WS, Bjorkman PJ (1995) The MHC class I homolog encoded by human cytomegalovirus binds endogenous peptides. Immunity 3 583-590 Fanger NA, Cosman D, Peterson L, Braddy SC, Maliszewski CR, Borges L (1998) The MHC class I binding proteins LIR-1 and LIR-2 inhibit Fc receptor-mediated signaling in monocytes. Eur J Immunol 28 3423-3434... 

The orexin receptors (0X1R and 0X2R) are G-protein coupled receptors expressed mainly in the brain. These receptors are believed to be involved in the regulation of the sleep-wake cycle and other behaviors in animals and humans. Activation of these two receptors by two endogenous peptides, orexin A and orexin B, promotes wakefulness in animals. Hence, blockade of orexin signaling by a small molecule antagonist may offer a new treatment for insomnia patients. Clinical evidence for this hypothesis was demonstrated in 2007 with the release of data from a Phase II insomnia trial from Actelion Pharmaceuticals (1). 

A class of immunoregulatory polypeptides produced by various cells types, but predominantly by mononuclear phagocytes activated by signals provided by exogenous pyrogens. These peptides act as endogenous pyrogens. 

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