24691
The endothelium forms the major interface between the blood and the CNS , and by a combination of low passive permeability and presence of specific transport systems , enzymes and receptors regulates molecular and cellular traffic across the barrier layer .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None