2757
Other groups received either an infusion of the selective NMDA receptor antagonist ( AP7 ; 10 nmol ; intra - mPFC ) or vehicle , 10 min prior to PILO preceding LFS600 , or prior to a supra - threshold LTD protocol ( 900 pulses , 1 Hz ; LFS900 ) .
 NMDA, AP7, PILO
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 NMDA, AP7, PILO