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Because alpha 5 has also been implicated in nicotine dependence behaviors in mice and can form functional receptors with alpha 3 beta 4 * , we also evaluated the role of the alpha 3 beta 4 alpha 5 * nAChR subtype in nicotine reward and somatic nicotine withdrawal signs by blocking the alpha 3 beta 4 * nAChR subtype in alpha 5 nAChR knockout mice with AuIB .
 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