4280
When the l - methadone - sensitive , opioid receptor is blocked by naloxone or tolerance has developed , than l - methadone can produce behavioral effects by a nonopioid mechanism .
 GENE: opioid 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: opioid receptor 
Answer:
 GENE: opioid receptor