18235
Because DA release induced by 5 micro M MeHg was associated with a significant percentage of cell death at 60 and 120min , 2 micro M MeHg was chosen for further characterization of release mechanisms .
 MeHg, MeHg
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 MeHg, MeHg