5909
Treatment of rat lung fibroblasts ( RFL6 ) with CoCl2 ( Co , 10 - 100 mu M ) , a chemical hypoxia reagent , enhanced LO mRNA expression and promoter activities .
 CoCl2, Co
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 CoCl2, Co