2500
Fentanyl , a prototypic mu - opiate receptor agonist , has been previously shown to produce a syndrome characterized by marked analgesia and locomotor stimulation as well as tachycardia , tachypnoea and behavioural arousal .
 GENE: mu - opiate receptor
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities: mu - opiate receptor 
Answer:
 GENE: mu - opiate receptor