2704
The present results demonstrate that CCK - 8 attenuates the effect of morphine on hippocampal LTP through CCK2 receptors and suggest an ameliorative function of CCK - 8 on morphine - induced memory impairment .
 Chemical: CCK - 8; Chemical: morphine; Chemical: CCK - 8; Chemical: morphine; Disease: memory impairment
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: CCK - 8; Chemical: morphine; Chemical: CCK - 8; Chemical: morphine; Disease: memory impairment