867
The present study investigated whether impacting early in development the hypothalamic - pituitary - adrenal axis , by exposing Mecp2 - 308 mutant pups to a low dose of corticosterone ( 50 micro g / ml , during the 1st week of life ) may contrast RTT - related abnormalities in neuroendocrine regulation and behavioural adaptation at adulthood .
 Chemical: corticosterone
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: corticosterone 
Answer:
 Chemical: corticosterone