Secretin: C~130~H~220~N~44~O~40~ (human). Mw: 3039.41; C~130~H~220~N~44~O~41~ (porcine). Mw: 3055.41. (human): (1) Secretin (porcine), 15-L-glutamic acid-16-glycine-; (2)L-Histidyl-L-seryl-L-α-aspartylglycyl-L-threonyl-L-phenylalanyl-L-threonyl-L-seryl-L-α-glutamyl-L-leucyl-L-seryl-L-arginyl-L-leucyl-L-arginyl-L-α-glutamylglycyl-L-alanyl-L-arginyl-L-leucyl-L-glutaminyl-L-arginyl-L-leucyl-L-leucyl-L-glutaminylglycyl-L-leucyl-L-valinamide.
(porcine): (1) Secretin (porcine): (2) L-Histidyl-L-seryl-L-α-aspartylglycyl-L-threonyl-L-phenylalanyl-L-threonyl-L-seryl-L-α-glutamyl-L-leucyl-L-seryl-L-arginyl-L-leucyl-L-arginyl-L-α-aspartyl-L-seryl-L-alanyl-L-arginyl-L-leucyl-L-glutaminyl-L-arginyl-L-leucyl-L-leucyl-L-glutaminylglycyl-L-leucyl-L-valinamide. CAS-108153-74-8 (human); CAS-17034-35-4 (porcine); CAS-1393-25-5 (2004).