3953
These data are consistent with the hypothesis that exercise - induced tachycardia results largely from beta 1 - receptor activation that is blocked by both cardioselective and nonselective drugs , whereas isoproterenol activates both beta 1 - and beta 2 - receptors so that after cardioselective blockade there remains a beta 2 - component that can be blocked with a nonselective drug .
 Disease: tachycardia; Chemical: isoproterenol
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:
 Disease: tachycardia; Chemical: isoproterenol