29459
RATIONALE : Nicotinic acetylcholine receptors ( nAChRs ) are a critical component of the cholinergic system of neurotransmission in the brain that modulates important physiological processes such as reward , cognition , and mood .
 Chemical: acetylcholine
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: acetylcholine