4884
We studied null mutant mice for six different GABA ( A ) - R subunits ( alpha 1 , alpha 2 , alpha 3 , alpha 4 , alpha 5 and delta ) .
 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: GABA