15591
Imipramine dimers were only found to be moderate inhibitors of the human serotonin transporter ( hSERT ) having IC ( 50 ) values in the micromolar region whilst the induction of cell death occurred independently of hSERT expression .
 Imipramine, serotonin
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 Imipramine, serotonin