21161
Preclinical data suggest that the 5 - hydroxytryptamine ( serotonin ) 6 ( 5 - HT6 ) receptor may be a potential target for the development of new therapies for treating cognitive dysfunctions in schizophrenia and other central nervous system disorders .
 5 - hydroxytryptamine, serotonin
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 5 - hydroxytryptamine, serotonin