30304
The treatment of 6 - OHDA - lesioned rats with GDNF microspheres and with both VEGF and GDNF microspheres resulted in improved results in the rotation behaviour test .
 6 - OHDA
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 6 - OHDA