Nomenclature	CCK 1 receptor	CCK 2 receptor
HGNC, UniProt	CCKAR, P32238	CCKBR, P32239
Potency order of endogenous ligands	CCK‐8 (CCK, P06307) ≫gastrin‐17 (GAST, P01350), desulfated cholecystokinin‐8>CCK‐4 (CCK, P06307)	CCK‐8 (CCK, P06307) ≥gastrin‐17 (GAST, P01350), desulfated cholecystokinin‐8, CCK‐4 (CCK, P06307)
Endogenous agonists	–	desulfated cholecystokinin‐8 [1135], gastrin‐17 (GAST, P01350) [845] – Mouse, CCK‐4 (CCK, P06307) [871], desulfated gastrin‐14 (GAST, P01350), desulfated gastrin‐17 (GAST, P01350), desulfated gastrin‐34 (GAST, P01350), desulfated gastrin‐71 (GAST, P01350), gastrin‐14 (GAST, P01350), gastrin‐34 (GAST, P01350), gastrin‐71 (GAST, P01350)
Selective agonists	A‐71623 [67] – Rat, JMV180 [971], GW‐5823 [772]	RB‐400 [129] – Rat, PBC‐264 [886] – Rat
Antagonists	lintitript (pIC50 8.3) [667]	–
Selective antagonists	devazepide (pIC50 9.7) [845] – Rat, T‐0632 (pIC50 9.6) [1935] – Rat, PD‐140548 (pIC50 8.6) [1817] – Rat, lorglumide (pIC50 6.7–8.2) [845, 875] – Rat	YF‐476 (pIC50 9.7) [201, 1927], GV150013 (pIC50 9.4) [2006], L‐740093 (pIC50 9.2) [1464], YM‐022 (pIC50 9.2) [1464], JNJ‐26070109 (pIC50 8.5) [1390], L‐365260 (pIC50 8.4) [1135], RP73870 (pIC50 8) [1181] – Rat, LY262691 (pIC50 7.5) [1632] – Rat
Labelled ligands	[3 H]devazepide (Antagonist) (pK d 9.7) [306], [125 I]DTyr‐Gly‐[(Nle28,31)CCK‐26‐33 (Agonist) [1599]	[3 H]PD140376 (Antagonist) (pK i 9.7–10) [849] – Guinea pig, [125 I]PD142308 (Antagonist) (pK d 9.6) [820] – Guinea pig, [125 I]DTyr‐Gly‐[(Nle28,31)CCK‐26‐33 (Agonist) [1599], [125 I]gastrin (Agonist), [3 H]gastrin (Agonist), [3 H]L365260 (Antagonist) (pK d 8.2–8.5) [1464], [125 I]‐BDZ 2 (Antagonist) (pK i 8.4) [25]