8787
Using a prenatal androgen ( PNA ) - treated mouse model of PCOS , we aimed to investigate negative and positive feedback effects of estrogens on the hypothalamic - pituitary axis regulation of LH .
 Chemical: androgen; Chemical: estrogens
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: androgen; Chemical: estrogens