Cholecystokinin peptides

CHOLECYSTOKININ PEPTIDES ARE FOUND IN THE CENTRAL NERVOUS SYSTEM... 

Emson PC, Lee CM, Rehfeld JF Cholecystokinin peptides vesicular localization and calcium dependent release from rat brain in vitro. Life Sci 26 2157-2162, 1980... 

Since cholecystokinin peptides show a neuroleptic-like profile in several screening tests for neuroleptics, cholecystokinin-dopamine interactions are of interest, especially the modulation of cholecystokinin release by dopamine receptors (Table 1). In the rat striatum both Di and D2 receptor activation was reported to increase, and both Di and D2 receptor blockade to depress, the release of the peptide. 

Seroogy K, Tsuruo Y, Hokfelt T, Walsh J, Fahrenkrug J, Emson PC, Goldstein M (1988) Further analysis of presence of peptides in dopamine neurons cholecystokinin, peptide histidine-isoleucine/vasoactive intestinal polypeptide and substance P in rat supramammillary region and mesencephalon. Exp Brain Res 72 523-534. 

Penke B, Zarandi M, Zsigo J, Toth GK, Kovacs K, Telegdy G. Synthesis of cholecystokinin peptides. Pept. Proc. Eur. Pept. Symp., 19th. 1987 447-450. 

The principal hormones of the human posterior pituitary include the two nonapeptides, oxytocin [50-56-6] and arginine vasopressin [11000-17-2] (antidiuretic hormone, ADH). Many other hormones, including opioid peptides (see Opioids, endogenous), cholecystokinin [9011-97-6] (CCK) (see Hormones, BRAIN oligopeptides), and gastrointestinal peptides, also have been located in mammalian neurohypophysis (6), but are usually found in much lower concentrations (7). Studies have demonstrated that oxytocin and vasopressin are synthesized in other human organs, both centrally and peripherally, and there is considerable evidence for their role as neurotransmitters (see Neuroregulators) (8). 

The BZ stmcture also has provided a molecular scaffold for a number of peptide receptor ligands (26). Antagonists for the cholecystokinin (CCK-A) receptor, eg, devazepide (65), the thyrotropin-releasing hormone (TRH) receptor, eg, midazolam (66), and the /i -opiate receptor, eg, tifluadom (67), as well as a series of ras famyl transferase inhibitors, eg, BZA-2B (68) (30) have been identified (Table 4). 

Other peptides that have been linked to the actions of ethanol are corticotropin-releasing factor, urocortin, leptin, cholecystokinin, melanocortins, and galanin (for reviews, see Cowen et al. 2004 Egli 2003 Thiele et al. 2003). 

D Peptides Enkephalins, endorphins, cholecystokinin, substance P (Many others have been implicated)... 

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... 

Cholelithiasis can develop as a result of decreased gallbladder contractility, especially in the absence of enteral or oral intake. Lack of intestinal stimulation reduces secretion of cholecys-tokinin, a peptide hormone secreted in the duodenum that induces gallbladder contractility. The best prevention of cholelithiasis is early initiation of enteral or oral feeding, as stated earlier (to stimulate secretion of cholecystokinin, gallbladder contraction and emptying, and intestinal motility). 

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