8631
As previously described for caffeine , the locomotor activating doses of paraxanthine more efficiently counteract the locomotor depressant effects of an adenosine A ( 1 ) than an adenosine A ( 2A ) receptor agonist .
 Chemical: caffeine; Chemical: paraxanthine; Chemical: adenosine; Chemical: adenosine
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: caffeine; Chemical: paraxanthine; Chemical: adenosine; Chemical: adenosine