18171
Channels responsible for slowly activating delayed - rectifier potassium current ( I ( Ks ) ) are composed of KCNQ1 and KCNE1 subunits , and these channels play a role in the repolarization of cardiac action potentials .
 potassium
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: Chemical 
Text: {0} 
Answer:
 potassium