2696
Cholecystokinin - octapeptide restored morphine - induced hippocampal long - term potentiation impairment in rats .
 Chemical: Cholecystokinin - octapeptide; Chemical: morphine
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: morphine