23677
This up - regulation of beta 1AR action was eliminated with 17 beta - estradiol addition to the media , directly implicating this hormone as a regulator of beta 1AR expression .
 17 beta - estradiol
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 17 beta - estradiol