4291
Role of 5 - hydroxytryptamine 1B ( 5 - HT1B ) receptors in the regulation of ethanol intake in rodents .
 Chemical: 5 - hydroxytryptamine; Chemical: ethanol
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: 5 - hydroxytryptamine, ethanol 
Answer:
 Chemical: 5 - hydroxytryptamine; Chemical: ethanol