23622
Further evidence for involvement of the dorsal hippocampus serotonergic and gamma - aminobutyric acid ( GABA ) ergic pathways in the expression of contextual fear conditioning in rats .
 Chemical: gamma - aminobutyric acid; Chemical: GABA
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: gamma - aminobutyric acid; Chemical: GABA