20533
Compound 4 exerted vasorelaxant activity at particularly low concentration and the vasorelaxant profile reached maximum at relatively low concentration , especially when compared with acetylcholine , the positive control .
 Chemical: acetylcholine
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: acetylcholine