Tachykinin-related peptides

A complete list of sequences for insect peptides up to 1997 is available [10,37], Insect tachykinin-related peptides are given in [73],... 

Tachykinins (TK), preferentially 10- or 11-peptides characterized by a conserved C-terminal pentapeptide amide consisting of -Phe-Xaa-Gly-Leu-Met-NH2 (Xaa Phe, Tyr, Val or He), but their length ranges between 9 and 42 aa. The tachykinin peptides are phylogenetically ancient and well conserved throughout evolution. Numerous stmcturaUy related tachykinin peptides such as tachykinin-related peptides (TKRP) and invertebrate tachykinins (inv.-TK) have been discovered from mammals, birds. 

Sousa, G. L., Lenz, P. H., HartUne, D. K., Christie, A. E. (2008) Distribution of pigment dispersing hormone- and tachykinin-related peptides in the central nervous system of the copepod crustacean Calanus finmarchicus. Gen Comp Endocrinol, 156,454-459. 

These are a family of peptides which include substance P, isolated in 1931 but only sequenced in 1971. This peptide has been extensively studied since it was the first major peptide to be extracted from brain but only now are useful antagonists becoming available. Two closely related peptides were then isolated from mammalian tissues and can be added to a number of other tachykinins, many of which are found in amphibians. The name tachykinins originated from the vasoactive effects of substance P but the nomenclature has been resolved into calling the three major mammalian peptides substance P, neurokinin A (NKA) and neurokinin B (NKB) with the corresponding receptors being numbered 1 to 3. The order of potencies at the three receptors as follows ... 

Mathe AA, Jousisto-Hanson J, Stenfors C, et al Effect of lithium on tachykinins, calcitonin gene-related peptide, and neuropeptide Y in rat brain. J Neurosci Res 26 233-237, 1990... 

Maggi CA, Theodorsson E, Santicioli P, Giuliani S (1992) Tachykinins and calcitonin gene-related peptide as cotransmitters in local responses produced by sensory nerve activation in the guinea pig isolated renal pelvis. Neuroscience 46 549-559... 

Substance P and Substance K are also known as tachykinins. They are a family of closely related peptides responsible for important biological actions including bronchoconstriction, salivation, vasodilatation. 

Sundler, F., Brodin, E., Ekblad, E. etal. (1985). Sensory nerve fibers Distribution of substance P, neurokinin A and calcitonin gene-related peptide. In Tachykinin Ant onists . (eds R, Hakason and F. Sundler). pp. 3-14, Elsevier Science, New York. 

New initiatives in developing migraine treatments include the use of TACHYKININ RECEPTOR ANTAGONISTS and CALCITONIN GENE-RELATED PEPTIDE RECEPTOR ANTAGONISTS. 

Kangrga I, Randic M (1990) Tachykinins and calcitonin gene-related peptide enhance release of endogenous glutamate and aspartate from the rat spinal dorsal horn slice. J Neurosci /0 2026-2038. 

Limited and/or weak staining is seen at select sites and in select species for a variety of other peptide antisera (e.g., peptide histidine-isoleucine, calcitonin gene-related peptide, the tachykinin family members substance P and neurokinin A, etc. (22, 55, 91, 99)). These various immunoreactivities, though not necessarily prominent in extent or amount, nevertheless suggest the presence of a wide diversity of potentially bioactive peptides in the nervous system of parasitic flatworms. This neurochemical complexity is illustrated in cestodes where 20 different peptide immunoreactivities outnumber the seven putative classical (small molecule) transmitters reported to date for this group in the trematodes there are approximately 24 different peptide immunoreactivities in a wide range of species. These numbers will no doubt continue to increase. 

Tachykinin gene-related peptides, tachy-kinins. 

Physalaamin Pyr-Ala-Asp-Pro-Asn-Lys-Phe-iyr-Gly-Leu-Met-NHj, an amphibian tachykinin from the skin of the South American frog Physalaemus fus-cumaculatus [V. Erspamer et al. Experentia 20 (1964) 489-490]. P. has also been identified as a tumor-related peptide in extracts of human lung small cell carcinoma [L.H.Lazarus etal. Science 219 (1983) 79-81]. It affects blood vessels and extravascular smooth muscle, stimulates exocrine secretion, and has a distinct neurotropic effect. The C-terminal hexapeptide from P. elicits full biological response in guinea pig ileum, while the presence of the five V-terminal amino acids is necessary for full expression of sialogogic activity. Conformational studies have been reported. [J.-L. Bernier et al. Eur. J.Biochem. 142 (1984) 371-377]... 

Kummer W. Retrograde neuronal labeling and double-staining immunohistochemistry of tachykinin and calcitonin gene-related peptide-immunoieactive pathways in the carotid sinus nerve of the guinea pig. J Auton Nerv Syst 1988 23 131-141. 

Several multi-ligand/multi-receptor systems are known in which multiple structurally related peptide hgands bind to various GPCRs that belong to a common receptor family. The neuropeptide Y family, the tachykinin system and the melanocortin system, just to mention a few, are known to exhibit important functions in the organism and therefore have been intensively investigated for years by SAR studies based on synthetically derived analogs. 

Biosynthesis. Two closely related genes encode the three mammalian tachykinins. The preprotachykinin A gene encodes both substance P and substance K, while the preprotachykinin B gene encodes neuromedin K (45—47). The active sequences are flanked by the usual double-basic amino acid residues, and the carboxy-terrninal amino acid is a glycine residue which is decarboxylated to an amide. As with most neuropeptide precursors, intermediates in peptide processing can be detected, but their biological activities are not clear (ca 1994). 

Substance P (SP) is a member of the family of tachykinin peptides that also includes neurokinin A and B. Their respective receptors are tachykinin NKl, tachykinin NK2 and tachykinin NK3. Substance P is best known as a pain neurotransmitter, but it also controls vomiting. In relation to emesis, its sites of localisation include the area postrema and the nucleus tractus solitarius. 

The tachykinins and related neurokinins are a series of peptides that are generally associated with physiological events leading to pain and inflammation [75]. These substances have affinities for certain receptors such as NK-1, NK-2 and NK-3 and manifest their activities as mediators of neurotransmission or neuromodulation in the central and peripheral nervous systems. 

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