28-Thr-31-nle-cholecystokinin (25-33) 77568-41-3 CCKTN Caerulein, 1-de(5-oxo-L-proline)-2-L-arginine-8-L-norleucine-, (R)- Cck (25-33), thr(28)-nle(31)- Cholecystokinin (25-33), thr(28)-nle(31)- Cholecystokinin (25-33), threonyl(28)-norleucine(31)-