Cholecystokinin peptides Neuropeptides

Smaller and larger peptides ( neuropeptides ) such as substance P. somatostatin, vasopressin, corticotropin-releasing factor (CRF). neuropeptide Y or cholecystokinin (CCK). 

Amino acid receptors Monoamine receptors Lipid receptors Purine receptors Neuropeptide receptors Peptide hormone receptors Chemokine receptors Glycoprotein receptors Protease receptors Metabotropic glutamate and GABAb receptors Adrenoceptors, dopamine and 5-HT receptors, muscarinic and histamine receptors Prostaglandin, thromboxane and PAF receptors Adenosine and ATP (P2Y) receptors Neuropeptide Y, opiate, cholecystokinin VIP, etc. Angiotensin, bradykinin, glucagon, calcitonin, parathyroid, etc. Interleukin-8 TSH, LH/FSH, chorionic gonadotropin, etc. Thrombin... 

Widerlov E, Kalivas PW, Abelson JL, et al Influence of cholecystokinin on central monoaminergic pathways. Regul Pept 6 99-109, 1983 Widerlov E, Dndstrom LH, Wahlestedt C, et al Neuropeptide Y and peptide YY as possible cerebrospinal markers for major depression and schizophrenia, respectively. J Psychiatr Res 22 69-79, 1988... 

The heterogeneity of dopaminergic neurons may also be judged by the fact that the cotransmitter systems involving dopamine and peptides are varied in the central nervous system. For example, in the corpus striatum, in addition to dopamine, acetylcholine, y-aminobutyric acid, serotonin, glutamate, and aspartate, one also finds peptides such as enkephalin, substance P, somatostatin, neuropeptide Y, cholecystokinin, neurotensin, and vasoactive intestinal peptide. Although many neuroleptics block dopamine receptors, they may have selective effects on the peptides and other parts of the brain. A few examples will be cited. 

Endopeptidase-24.II (EC 3.4.24.11 NELP neutral endopeptidase neprilysin, enkephalinase) is a zinc-metalloproteinase, found both in soluble and plasma membrane forms. It is an important enzyme in neuropeptide degradation. Notable neuropeptide substrates include tachykinins (substance P, neurokinin A, neurokinin B), endothelins (ET-1, ET-2, ET-3), atrial natriuretic peptide, neurotensin, somatostatin and cholecystokinins. 

Shen T, Kaya N, Zhao FL, Lu SG, Cao Y, et al. 2005. Coexpression patterns of the neuropeptides vasoactive intestinal peptide and cholecystokinin with the transduction molecules alpha-gustducin and T1R2 in rat taste receptor cells. Neuroscience 130 229-238. 

Fig. 1. The C-terminal structure of members of the gastrin family. The members are characterized by the same active site, i.e., the C-terminal tetrapeptide amide (shown in the internal box). Another characteristic is an O-sulfated tyrosyl residue close to the active site. In gastrin peptides the sulfated tyrosyl residue is located in position six (as counted from the C-terminus) in cholecystokinins it is position seven. The frog skin peptide caerulein therefore acts as cholecystokinin in mammals. Cionin is a neuropeptide from the protochordate, Ciona intestinalis. Cionin is unique in having O-sulfated tyrosyl residues in both positions six and seven. The cionin structure is therefore likely to correspond to that of the common ancestor of gastrin and cholecystokinin.

Table 2 summarizes transmitters/peptides observed in tufted cells. As noted, large populations of tufted cells contain the neuropeptide cholecystokinin (CCK) (Seroogy et al. 1985). One study using in situ hybridization detected substance P transcripts in some external tufted cells and in up to half of the mitral cells in MOB of rat (Warden... 

A second study of A. suum, in which 31 antisera were tested, showed positive immunoreactivity with antisera to 11 peptides pancreatic polypeptide, peptide YY, neuropeptide Y, gastrin, cholecystokinin, substance P, atrial natriuretic peptide, salmon gonadotropin-releasing hormone, mammalian gonadotropin-releasing hormone, chromogranin A, and FMRFamide (192). 

Gastrin family, a member of the gastroen-teropancreatic peptide families. This family comprises the mammalian hormones gastrin and cholecystokinin, the pro-tochordean neuropeptide cionin, and... 

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