17834
This study shows that alpha 3 beta 4 * nAChRs mediate nicotine reward and physical nicotine withdrawal , but not acute nicotine behaviors or affective nicotine withdrawal signs in mice .
 Chemical: nicotine; Chemical: nicotine; Chemical: nicotine; Chemical: nicotine
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: nicotine; Chemical: nicotine; Chemical: nicotine; Chemical: nicotine