13807
Our results showed that an ultra - low concentration of ( - ) - naloxone ( 0 . 001 nM ) and several concentrations of ( + ) - naloxone ( 0 . 01 - 10 nM ) enhanced DAMGO - stimulated guanosine - 5 ' - 0 - ( gamma - thio ) - triphosphate incorporation in parabrachial sections in vitro .
 Chemical: ( - ) - naloxone; Chemical: ( + ) - naloxone; Chemical: DAMGO; Chemical: guanosine - 5 ' - 0 - ( gamma - thio ) - triphosphate
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: ( - ) - naloxone; Chemical: ( + ) - naloxone; Chemical: DAMGO; Chemical: guanosine - 5 ' - 0 - ( gamma - thio ) - triphosphate