24397
Serotonin ( 5 - HT ) in the Regulation of Depression - Related Emotionality : Insight from 5 - HT Transporter and Tryptophan Hydroxylase - 2 Knockout Mouse Models .
 Chemical: Serotonin; Chemical: 5 - HT; Chemical: 5 - HT; Chemical: Tryptophan
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: Serotonin; Chemical: 5 - HT; Chemical: 5 - HT; Chemical: Tryptophan