17604
The objective of the present study was to examine the social influences on cocaine self - administration in isolated and socially housed rats , under conditions where the socially housed rats were tested simultaneously with their partner in the same chamber .
 Chemical: cocaine
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: cocaine