Opioid-related peptides

Several peptides are related in different ways to these classical opioid peptides. FMREamide (Phe-Met-Arg-Phe-NH2) contains the first four amino acids of enkephalin and is active in various invertebrates (58) FMREamide-related peptides also have been located in the mammalian brain. Although these... 

There are dozens of presynaptic receptors for endogenous peptides. This review will focus on receptors for four peptides or peptide families the opioid peptides, neuropeptide Y and related peptides, adrenocorticotropic hormone (corticotropin, ACTH), and the orexins. This choice is representative, since part of the receptors inhibit and part of them facilitate transmitter release moreover, the receptors under consideration are coupled to the major G proteins, namely Gl/(), Gs and Gq (Table 1). 

Koch, G. and Brantl, V. 1990. Binding of (3-casomorphins to opioid receptors. In (3-Casomorphins and Related Peptides (F. Nyberg and V. Brantl, eds), pp. 43-52. Fyris-Tryck AB, Uppsala. 

Paakkari, I., Jarvinen, A., Antila, P., Mattila, M.J., and Pihlanto-Leppala, A. 1994. Opioid effects of the milk whey-protein derived peptides a- and (3-lactorphin. In 3-Casomorphins and Related Peptides. Recent Development (V. Brand and H. Teschemacher, eds), pp. 33-37. VCH, Weinheim. 

Yoshikawa, M., Tani, F., Shiota, A., Usui, H., Kurahashi, K., and Chiba, H. 1994. Casoxin D, an opioid antagonist/ileum-contracting/vasorelaxing peptide derived from human as[-casein. In (3-Casomorphins and Related Peptides Recent Developments (V. Brantl and H. Teschemacher, eds), pp. 43-48. VCH, Weinheim. 

Eflington HC, Cotter MA, Cameron NA, Ross RA (2002) The effect of cannabinoids on capsaicin-evoked caldtonin gene-related peptide (CGRP) release from the isolated paw skin of diabetic and non-diabetic rats. Neuropharmacology 42 966-975 Endres-Becker J, HeppenstaU PA, Mousa SA, Labuz D, Oksche A, Schafer M, Stein C, Zollner C (2007) Mu-opioid receptor activation modulates transient receptor potential vanilloid 1... 

Islet tissue contains a variety of peptides which are stored in pancreatic neurons, nerve fibres and secretory cells and which may, when released, also modulate insulin secretion. Among these are VIP, PHI, GRP, NPY, galanin, CCK, calcitonine-gene-related peptide (CGRP), substance P and opioid... 

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. 

Negri L, Erspamer GF, Severinl C, et al. Dermorphin-related peptides from the skin of Phyllomedusa bicolor and their amidated analogues activate two p opioid receptor subtypes that modulate antinociceptlon and catalepsy In the rat. Proc Natl Acad Sci USA 1992 89 7203-7207. 

A 17 amino acid long peptide sequentially related to opioid peptides in particular dynorphin A. OFQ/N is inactive at the 5, k, and p opioid receptors, but binds to its own NOP receptor (formerly ORL-1, for opioid receptor like-1). In contrast to opioid peptides, OFQ/N has no direct analgesic properties. OFQ/N is the first example for the discovery of a novel neurotransmitter from tissue extracts by using an orphan receptor as bait. Centrally administered in rodents, OFQ/N exerts anxiolytic properties. OFQ/N agonists and antagonists... 

Delta receptors are relatively selective for two related penta-peptides, methionine enkephalin and leucine enkephalin (met- and leu-enkephalin), which were isolated from porcine brain (Hughes 1975). Both met- and leu-enkephalin inhibit electrically induced contractions of guinea pig ileum, an effect that mimics those effects seen with opioid drugs, and is naloxone reversible. The enkephalins are processed posttranslational ly from proenkephalin, and secreted from central and peripheral neurons and endocrine cells in the adrenal medulla. 

Wilkes BC, Schiller, PW. Comparative analysis of various proposed models of the receptor-bound conformation of TIP(P)-related opioid antagonists. Biopolymers (Peptide Sci) 1995 37 391-400. 

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