2751
We investigated in this study the possible engagement of locus coeruleus of the pons in this phenomenon , using male Sprague - Dawley rats anesthetized with ketamine .
 Chemical: ketamine
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: ketamine