22125
RESULTS : Administration of naltrexone ( intravenously ) and beta - funaltrexamine ( subcutaneously ) , as well as intracranial injection of naltrexone into the VTA did not prevent the initiation of dopamine release by intravenous ethanol administration , but prevented it from being as prolonged .
 Chemical: naltrexone; Chemical: beta - funaltrexamine; Chemical: naltrexone; Chemical: dopamine; Chemical: ethanol
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: naltrexone; Chemical: beta - funaltrexamine; Chemical: naltrexone; Chemical: dopamine; Chemical: ethanol