23081
When pups were weaning , cortex and hippocampal gene expressions of brain - derived neurotrophic factor ( BDNF ) of the different isoforms of the thyroid hormone ( TH ) receptors ( TRs ) were evaluated .
 Chemical: thyroid hormone
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: thyroid hormone