30451
NSDA neurons displayed significant axon terminal degeneration ( as indexed by decreases in DA , tyrosine hydroxylase ( TH ) and DA transporter concentrations in the striatum ) as well as loss of TH - immunoreactive ( IR ) neurons in the substantia nigra ( SN ) following MPTP , whereas TIDA neurons revealed no overt axon terminal pathology or loss of TH - IR cell bodies .
 Chemical: tyrosine; Chemical: MPTP
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
 Entities: tyrosine, MPTP 
Answer:
 Chemical: tyrosine; Chemical: MPTP