5723
We examined the hypothesis that the coronary vasomotor responses to etomidate ( ETO ) , propofol ( PRO ) , and sodium thiopental ( STP ) are mediated through contrasting effects on the resting nitric oxide ( NO ) - dependent vasodilator tone that opposes adrenergic vasoconstrictor activity in the intact dog .
 None
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
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