2697
Cholecystokinin - octapeptide ( CCK - 8 ) , which is a typical brain - gut peptide , exerts a wide range of biological activities on the central nervous system .
 Chemical: Cholecystokinin - octapeptide; Chemical: CCK - 8
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Chemical: Cholecystokinin - octapeptide; Chemical: CCK - 8