25752
This study investigated the effect of Oligonol supplementation on circulating levels of prostaglandin E2 ( PGE2 ) and cyclooxygenase ( COX ) - 2 , as well as body temperature , after heat stress in 17 healthy human male volunteers ( age , 21 . 6 +/- 2 . 1 years ) .
 Chemical: prostaglandin E2; Chemical: PGE2
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 Chemical: prostaglandin E2; Chemical: PGE2