7181
Thus , natural food reward and systemic ghrelin activate mu and kappa opioid receptor pathways in the VTA , respectively , resulting in opposite influences on dopamine release in the NAc .
 Chemical: dopamine
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: dopamine