3701
These tachykinins , in turn , initiate a micturition reflex by stimulating NK1 and NK2 receptors .
 Chemical: tachykinins
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: tachykinins