Intestinal Polypeptide

Melatonin [73-31-4] C 2H N202 (31) has marked effects on circadian rhythm (11). Novel ligands for melatonin receptors such as (32) (12), C2yH2gN202, have affinities in the range of 10 Af, and have potential use as therapeutic agents in the treatment of the sleep disorders associated with jet lag. Such agents may also be usehil in the treatment of seasonal affective disorder (SAD), the depression associated with the winter months. Histamine (see Histamine and histamine antagonists), adenosine (see Nucleic acids), and neuropeptides such as corticotropin-like intermediate lobe peptide (CLIP) and vasoactive intestinal polypeptide (VIP) have also been reported to have sedative—hypnotic activities (7). 

CGRP is widely distributed throughout the peripheral and central nervous systems and is found ia sensory neurons and ia the autonomic and enteric nervous systems. In many iastances CGRP is co-localized with other neuroregulators, eg, ACh ia motor neurons, substance P, somatostatin, vasoactive intestinal polypeptide (VIP), and galanin ia sensory neurons. It is also present ia the CNS, with ACh ia the parabigeminal nucleus and with cholecystokinin (CCK) ia the dorsal parabrachial area. CGRP functions as a neuromodulator or co-transmitter. 

VIPoma stands for vasoactive intestinal polypeptide-secreting tumour. VIPomas are rare neuroendocrine tumours located in the pancreas. 

The release of some peptides may differ from that of other transmitters, depending on the firing rate of the neurons. The large vesicles needed to store a peptide may need a greater rate of depolarisation for membrane fusion and release of the contents. In the salivary gland the release of vasoactive intestinal polypeptide requires high-frequency stimulation whereas acetylcholine is released by all stimuli. Due to the complexities and problems of access to CNS synapses it is not known if the same occurs here but there is no reason why this should not. In sensory C-fibres a prolonged stimulus appears to be a prerequisite for the release of substance P. 

Foster, N. and Lee, D.L. (1996) A vasoactive intestinal polypeptide-like protein excreted/secreted by Nippostrongylus brasiliensis and its effect on contraction of uninfected rat intestine. Parasitology 112, 97-104. 

Wood, C.L., and O Dorisio, M.S. (1985) Covalent cross-linking of vasoactive intestinal polypeptide to its receptors on intact human lymphoblasts./. Biol. Chem. 260, 1243-1247. 

The number of neural genes known to contain CREs is growing as more and more genes are cloned. Prominent examples are tyrosine hydroxylase, c-fos, proenkephalin, prodynorphin, somatostatin and vasoactive intestinal polypeptide (VIP). Expression of these genes has been... 

Acetylcholine works with other neurotransmitters (i.e., cyclic guanylate monophosphate, cyclic adenosine monophosphate, vasoactive intestinal polypeptide) to produce penile arterial vasodilation and ultimately an erection. 

Figure 2.8. Scheme of a chimeric peptide with examples for each of the distinct domains. 0X26, anti-rat transferrin receptor monoclonal antibody (mAh) 84-15, anti-human insulin receptor mAh cHSA, cationized human serum albumin VIP, vasoactive intestinal polypeptide DALDA, dermorphin analogue NGF, nerve growth factor BDNF, brain-derived neurotrophic factor PNA, peptide nucleic acid (3-gal, (3-galactosidase. 

Among the peptide-based payloads that have been delivered is an analogue of the 28-amino acid peptide Vasoactive Intestinal Polypeptide (VIP) [89,95]. VIP is suitable for the... 

BDNF, brain derived neurotrophic factor CBF, cerebral blood flow GDNF, glial cell line derived neurotrophic factor NGF, nerve growth factor TfR, transferrin receptor VIP, vasoactive intestinal polypeptide. 

Additional impurities, such as glucagon, somatostatin, pancreatic polypeptide and vasoactive intestinal polypeptide, are present in most conventional insulin preparations at lower levels. The presence of such contaminants can impact upon product safety and efficacy in a number of ways. 

Cutler DJ, Haraura M, Reed HE, et. al 2003 The mouse VPAC2 receptor confers suprachiasmatic nuclei cellular rhythmicity and responsiveness to vasoactive intestinal polypeptide in vitro. Eur J Neurosci. 17 197—204 Ebling FJ 1996 The role of glutamate in the photic regulation of the suprachiasmatic nucleus. Prog Neurobiol 50 109-132... 

Thyrotropin-releasing hormone Vasoconstrictive intestinal polypeptide... 

One of the surprising findings of recent brain and central nervous system research is that chemical substances previously considered to be exclusive to ihe province of the brain have been found in organs outside the nervous system (e.g., somatostatin, neurotensin, and enkephalins have been found in the gut), and conversely, that other substances active in other organs, but not previously associated with the central nervous system, have been found in the latter (e.g.. gastrin, vasoactive intestinal polypeptide (VIP), and choiecystokinin. traditionally associated with the gastrointestinal tract, but now found in the central nervous system). 

Additionally, we demonstrated increased substance P and reduced vasoactive intestinal polypeptide levels, and increased numbers of serotonin-positive enteroendocrine cells that correlated exactly with H. diminuta expulsion following primary and secondary infections (McKay et al., 1990a, 1991) whether these neu-rohormonal changes are a cause or an effect of worm rejection remains to be clarified. Indeed, the role of the enteric nervous system needs to be incorporated into the consideration of the enteric response to cestode infection (McKay and Fairweather, 1997). 

Finally, peptides such as galanin, leptin, neuropeptide Y, vasoactive intestinal polypeptide (VIP), and pituitary adenylate cyclase-activating polypeptide (PACAP) have been identified in various areas of the CNS. These and other peptides may affect various CNS functions, either by acting directly as neurotransmitters or by acting as cotransmitters moderating the effects of other neurotransmitters.7 24,27,34... 

Wei Y, Mojsov S. Tissue specific expression of different human receptor types for pituitary adenylate cyclase activating polypeptide and vasoactive intestinal polypeptide implications for their role in human physiology. J Neuroendocrinol 1996 8 811-817. 

Usdin TB, Bonner TI, Mezey E. Two receptors for vasoactive intestinal polypeptide with similar specificity and complementary distributions. Endocrinology 1994 135 2662-2680. 

Riou F, Cespuglio R, Jouvet M. Hypnogenic properties of the vasoactive intestinal polypeptide in rats. CR Acad Sci III 1981 293 679-682. 

Drucker-Colin R, Bemal-Pedraza J, Femandez-Cancino F, Oksenberg A. Is vasoactive intestinal polypeptide (VIP) a sleep factor Peptides 1984 5 837-840. 

Obal F Jr, Sary G, Alfoldi P, Rubicsek G, Obal F. Vasoactive intestinal polypeptide promotes sleep without effects on brain temperature in rats at night. Neurosci Lett 1986 64 236-240. 

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