27824
Here we ask : does the metaplastic effect of nicotine on cocaine also apply in the amygdala , a brain region that is involved in the orchestration of emotions and in drug addiction ?
 nicotine, cocaine
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 nicotine, cocaine