Peptides endogenous vasoactive

Because renal vasodilatation and hyperfiltration are often associated with a natriuretic response, a number of activators or inhibitors of endogenous vasoactive systems can cause increased NaCl excretion, and some of these may be developed into compounds of clinical interest in special situations. Such agents include natriuretic pqDtides most notably B-type natriuretic peptide (nesiritide), neutral endopeptidase (NEP) inhibitors (thiorphan, phosphoramidon), mixed NEP and ACE inhibitors (omapatrilat), guanylin and uroguanylin, kinins, prostaglandins of the E series, adrenomedullin, relaxin, prolactin, and others. 

Autacoids Endogenous substances with compiex physioiogic and pathophysioiogic functions commoniy interpreted to inciude histamine, serotonin, prostagiandins, and vasoactive peptides... 

A. Classification and Prototypes Vasoactive peptides comprise a large class of endogenous substances that function as neurotransmitters as well as local and systemic hormones. The better-known peptides include angiotensin, bradykinin, atrial natriuretic peptide, endothelin, vasoactive intestinal peptide, substance P, calcitonin gene-related peptide, vasopressin, glucagon, and several opioid peptides. Vasopressin is discussed in Chapters 15 and 37, the opioid peptides in Chapter 31, and glucagon in Chapter 41. The peptides discussed in this chapter and their effects are summarized in Table 17-1. 

In addition to the endogenous opiate peptides, several other peptides function as neurotransmitters (e.g., substance P, vasoactive intestinal peptide). These agents are generally cleaved from larger peptide precursors. They can assume a variety of three dimensional shapes, making it difficult to assess the chemistry of peptide-receptor interactions. For this reason, no chemical agonists (other than morphine) or antagonists have been identified for peptide receptors. 

Urotensin II Receptor (GPR14). The vasoactive cyclic peptide urotensin II (U-II) is the endogenous ligand of the G protein-coupled orphan receptor GPR14. Structure-activity relationships from 25 peptide analogs, which mobilize intracellular calcium in GPR14-transfected CHO cells, and the... 

Hormones and neuronal activity affect brain glycogen metabolism. Glycogen is affected by hormones endogenous to the brain including vasoactive intestinal peptide and noradrenaline, as well as circulating hormones, such as insulin [61, 63, 64]. The mechanism whereby insulin exerts an effect on glycogen metabolism in brain has not been determined [63]. Glycogen metabolism in brain, unlike in other tissues, is controlled locally, due to differential local metabolic rates. 

Leceta J, Martinez C, Delgado M, Garrido E, Gomariz RP (1996) Expression of vasoactive intestinal peptide in lymphocytes A possible endogenous role in the regulation of the immune system. Adv Neuroimmunol 6 29-36. 

Octreotide, a synthetic octapeptide analog of endogenous somatostatin, is prescribed for the symptomatic treatment of carcinoid tumors and vasoactive intestinal peptide-secreting tumors (VIPomas). Metastatic intestinal carcinoid tumors secrete excessive... 

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