1565
Endothelial function was assessed by acetylcholine - induced vasorelaxation and phenylephrine - induced vasoconstriction in aortic segments .
 acetylcholine, phenylephrine
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 acetylcholine, phenylephrine