CCK-4 (holecistokininski tetrapeptid, Trp-Met-Asp-Phe-NH2; ili PTK7) je peptidni fragment izveden iz većeg peptidnog hormona holecistokinina. Za razliku od holecistokina koji ima niz uloga u gastrointestinalnom sistemu kao i u centralnom nervnom sistemu, CCK-4 deluje prvenstveno u mozgu kao stimulator anksioznosti. On pokazuje slabe GI efekte, za razliku od CCK-8 ili polipeptida pune dužine, CCK-58.
CCK-4 proizvodi jake simptome anksioznosti u malim dozama, kao što je 50 μg,[1] i često se koristi u naučnim istraživanjima za indukovanje paničnih napada s ciljem testiranja novih anksiolitika.[2][3][4][5] Pošto je on peptid, CCK-4 mora biti administriran putem injekcije. U telu se brzo razlaže, tako da ima kratkotrajno dejstvo.[6] Brojni sintetički analozi sa modifikovanim osobinama su poznati.[7][8][9][10][11][12][13][14][15][16][17]
^Eser D, Leicht G, Lutz J, Wenninger S, Kirsch V, Schüle C, Karch S, Baghai T, Pogarell O, Born C, Rupprecht R, Mulert C (2007). „Functional neuroanatomy of CCK-4-induced panic attacks in healthy volunteers”. Human Brain Mapping. 30 (2): 511—22. PMID18095276. doi:10.1002/hbm.20522.
^Koulischer D, Moroder L, Deschodt-Lanckman M (1982). „Degradation of cholecystokinin octapeptide, related fragments and analogs by human and rat plasma in vitro”. Regulatory Peptides. 4 (3): 127—139. PMID6291099. doi:10.1016/0167-0115(82)90080-5.
^Blommaert AG, Dhôtel H, Ducos B, Durieux C, Goudreau N, Bado A, Garbay C, Roques BP (1997). „Structure-based design of new constrained cyclic agonists of the cholecystokinin CCK-B receptor”. Journal of Medicinal Chemistry. 40 (5): 647—58. PMID9057851. doi:10.1021/jm9603072.
^Bellier B, Million ME, DaNascimento S, Meudal H, Kellou S, Maigret B, Garbay C (2000). „Replacement of glycine with dicarbonyl and related moieties in analogues of the C-terminal pentapeptide of cholecystokinin: CCK(2) agonists displaying a novel binding mode”. Journal of Medicinal Chemistry. 43 (20): 3614—23. PMID11020275. doi:10.1021/jm0000416.
^Bellier B, Garbay C (2003). „How a single inversion of configuration leads to a reversal of the binding mode: proposal of a novel arrangement of CCK2 ligands in their receptor, and contribution to the development of peptidomimetic or non-peptide CCK2 ligands”. European Journal of Medicinal Chemistry. 38 (7-8): 671—86. PMID12932898. doi:10.1016/S0223-5234(03)00112-0.
^Bellier B, Crété D, Million ME, Beslot F, Bado A, Garbay C, Daugé V (2004). „New CCK2 agonists confirming the heterogeneity of CCK2 receptors: characterisation of BBL454”. Naunyn-Schmiedeberg's Archives of Pharmacology. 370 (5): 404—13. PMID15480577. doi:10.1007/s00210-004-0969-7.
^Proskuriakova TV; Bespalova ZhD; Pal'keeva ME; Petrichenko OB; Pankratova NV; Shokhonova VA; Anokhina IP (2005). „[Biological activity of cholecystokinin-(30-33) tetrapeptide analogs]”. Bioorganicheskaia Khimiia (на језику: руски). 31 (2): 130—9. PMID15889786.
^Anokhina IP; Proskuriakova TV; Bespalova ZhD; Pal'keeva ME; Shokhonova VA; Petrichenko OB (2006). „[Effect of a cholecystokinin tetrapeptide analogue on opioid reception under acute and chronic morphine administration]”. Bioorganicheskaia Khimiia (на језику: руски). 32 (3): 276—83. PMID16808170.
^Noble F (2007). „Pharmacology of CCKRs and SAR studies of peptidic analog ligands”. Current Topics in Medicinal Chemistry. 7 (12): 1173—9. PMID17584139. doi:10.2174/156802607780960447.
^García-López MT, González-Muñiz R, Martín-Martínez M, Herranz R (2007). „Strategies for design of non peptide CCK1R agonist/antagonist ligands”. Current Topics in Medicinal Chemistry. 7 (12): 1180—94. PMID17584140. doi:10.2174/156802607780960537.
^Kalindjian SB, McDonald IM (2007). „Strategies for the design of non-peptide CCK2 receptor agonist and antagonist ligand”. Current Topics in Medicinal Chemistry. 7 (12): 1195—204. PMID17584141. doi:10.2174/156802607780960500.