1754
At dose levels of ( + ) - propranolol which attenuated the responses to isoprenaline , there was a significant prolongation of the PR interval of the electrocardiogram . 3 .
 Chemical: propranolol; Chemical: isoprenaline
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Disease, Chemical 
Text: {0} 
Answer:
 Chemical: propranolol; Chemical: isoprenaline